Nextcloud
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Unauthenticated OS command injection in the Collabora Online Built-in CODE Server Nextcloud app (richdocumentscode) before 26.4.303 allows remote attackers to execute arbitrary commands on the Nextcloud host via proxy.php, but only while the bundled CODE server process is not running - the window right after a restart, during startup, or following a crash. The CVSS 4.0 score is 9.2 and the CVE record attributes exploitation during September and October 2026, making this a genuine high-priority issue rather than a paper-tiger high-severity finding; the practical barrier is timing, not authentication, since the CVSS vectors carry PR:N/UI:N and an attacker can simply poll the endpoint until CODE is down. Standalone Collabora Online servers do not ship proxy.php and are explicitly not affected - the exposure is confined to Nextcloud instances with the richdocumentscode app, and the flaw is distinct from CVE-2025-66208.
Unauthenticated vector-store tampering in Nextcloud MCP Server before 0.117.2 lets any network attacker who can reach the /webhooks/nextcloud endpoint delete or force re-indexing of Qdrant semantic-search embeddings for arbitrary users. Because WEBHOOK_SECRET defaults to None and startup never enforces it, the webhook receiver processes forged POSTs and trusts the attacker-supplied user.uid, so looping over document IDs can wipe the entire search index for all users. A working proof-of-concept is published in the GHSA advisory; publicly available exploit code exists, though there is no public exploit identified in CISA KEV.
Cross-project folder hijacking in OpenProject before 17.3.3 and 17.4.1 lets a project-admin abuse an insecure direct object reference (CWE-639) to take over another project's managed Nextcloud or OneDrive storage folder. By PATCHing the storages_project_storage[project_folder_id] parameter on /projects/<id>/settings/project_storages/<ps_id>, an attacker writes a victim project's folder ID into their own ProjectStorage row, and the next managed-folder sync rewrites the target folder's ACL to the attacker's project member list. CVSS is 9.9 and the issue carries a scope change, but there is no public exploit identified at time of analysis and it is not on CISA KEV.
Blind SQL injection in the Nextcloud Tables app affects versions 0.9.0 through 0.9.6 and 1.0.0 through 1.0.1, allowing authenticated users with access to the Tables app to inject SQL into the ORDER BY clause of database queries. The flaw permits bit-by-bit data extraction or time-based exfiltration against the underlying database, and no public exploit identified at time of analysis. Patches are available in versions 0.9.7 and 1.0.2.
SQL injection in the Nextcloud Tables app allows authenticated users with access to the Tables feature to execute arbitrary SQL queries against the backend database via a stored injection vector. Although a 20-byte length limit is imposed on the injected payload, carefully crafted input can break out of this restriction, enabling data extraction and modification. No public exploit identified at time of analysis, and the issue is not listed in CISA KEV.
Authentication bypass in the Nextcloud user_oidc app (versions 1.3.6 up to but not including 8.4.0) lets users that were originally provisioned via LDAP continue to authenticate through OpenID Connect even after their account has been deleted. Because an internal LDAP-enabled check was inverted, deletion did not correctly revoke OIDC login for affected accounts, meaning a de-provisioned user with valid OIDC credentials could regain access to the platform. There is no public exploit identified at time of analysis and EPSS is very low (0.03%), but the flaw is a genuine access-control gap fixed in version 8.4.0.
Improper authorization in the Nextcloud Server CalDAV backend allows an authenticated user who knows another user's principal URL to gain full read/write access to that user's calendar in versions 32.0.0 to before 32.0.9 and 33.0.0 to before 33.0.3. The flaw was reported via HackerOne (report 3545964) and patched in PR 59962 by introducing dedicated ProxyRead/ProxyWrite ACL-aware classes; no public exploit identified at time of analysis and the issue is not listed in CISA KEV.
Authentication bypass in Nextcloud's User OIDC app (versions 0.3.0-3.0.x, 5.0.0-5.0.x, and 6.0.0-6.3.x) allows a malicious ID4me authority to impersonate arbitrary users due to missing JWT signature verification in the ID4me login flow. The flaw stems from a literal 'TODO: VALIATE SIGNATURE!' code comment that left ID tokens accepted without cryptographic validation, enabling identity spoofing once a victim is redirected through the attacker-controlled authority. No public exploit identified at time of analysis, and the issue is not listed in CISA KEV.
Authorization bypass in Windmill 1.56.0-1.614.0 enables Operator role users to escalate privileges to remote code execution. Operators can bypass documented role restrictions via unprotected backend API endpoints to create/modify scripts, flows, and apps, then execute arbitrary code through the jobs API. Public exploit code exists (GitHub: Chocapikk/Windfall). EPSS data unavailable, but the low attack complexity (AC:L), network access vector (AV:N), and availability of weaponized POC indicate elevated real-world risk for self-hosted Windmill deployments with Operator-level users.
Authentication bypass in OpenClaw's Nextcloud Talk plugin versions ≤2026.2.2 allows remote unauthenticated attackers to bypass DM and room allowlists by spoofing display names. Attackers can change their Nextcloud display name to match an allowlisted user ID, gaining unauthorized access to restricted conversations without authentication. EPSS score is low (0.05%, 16th percentile), indicating low observed exploitation probability. No active exploitation confirmed; vulnerability was responsibly disclosed by AISLE Research Team and patched in version 2026.2.6.
Nextcloud server is an open source home cloud implementation. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. This OS Command Injection vulnerability could allow attackers to execute arbitrary operating system commands on the host.
File owners on Nextcloud Server cannot release TYPE_TOKEN file locks that other users have placed on their files, leaving the file locked with no in-product recovery path; administrators currently have to clear the orphaned lock directly in the database. The defect is an access-control gap (CWE-284) reachable over the network by any authenticated user who can acquire a token lock, typically in shared-folder or multi-user collaboration scenarios, and it is availability-only - no confidentiality or integrity impact - as reflected in the assessed vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. No public exploit code has been identified and there is no evidence of active exploitation, so despite a 6.5 base score this behaves as an accidental or malicious file-lockout rather than a scalable remote attack.
Persistent sidebar layout manipulation in the Nextcloud Collectives app allows an authenticated user with page-edit permission to submit oversized text containing line breaks to the page emoji update endpoint, which accepts the value without length or character validation. When another user subsequently views the affected collective page, the unvalidated emoji string overflows and breaks the rendered sidebar, hiding other navigation items from view. The impact is confined to client-side layout integrity with no confidentiality or availability loss (CVSS 3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N, published vector 2.4 with PR:H), making this a genuinely low-risk issue; no public exploit code has been identified at time of analysis, and it applies only where the optional Collectives app is installed.
Authorization bypass in Nextcloud Server (Circles feature) lets an authenticated user retrieve the membership list of a circle they do not belong to, exposing membership information for Nextcloud Server 32.0.0 through 34.0.0, as detailed in HackerOne report 3484601. Exploitation is gated by a severe practical constraint: the attacker must supply an existing circle's unique identifier, which lives in a 62^15-space (roughly 90-bit) keyspace, so the CVSS 3.1 score reflects high attack complexity rather than an easily reachable bypass and no public exploit has been identified at time of analysis. Impact is limited to confidentiality of one circle's member list; no modification, deletion, or service disruption is possible, making this a low-priority issue for most deployments.
Metadata disclosure in Nextcloud Server's Photos app smart albums allows an authenticated user to enumerate file names, IDs, and other metadata from a sharer's folders that were never intended to be included in the shared album. This moderate, tightly scoped authorization flaw (CWE-284) occurs because the smart album builds its file listing using the viewing user's photosSourceFolders search configuration instead of the album owner's configuration; an attacker who has been granted a filter-based smart album share can modify their own folder settings to widen the search scope. No public exploit code is identified at time of analysis, and the independent assessment limits impact to metadata (not file content) within the filter-reachable scope; it cannot reach files of users who have not shared such an album.
Blind server-side request forgery in the Nextcloud Circles (Teams) app lets any unauthenticated remote user force the Nextcloud Server to issue an outbound GET request to an attacker-chosen internal or private address through the public endpoints POST /apps/circles/event/ and POST /apps/circles/incoming/. The flaw sits in remote-instance signature verification, which fetches the attacker-supplied keyId URL before trust in the remote instance is established and explicitly permits local and private address ranges, bypassing Nextcloud's core SSRF protections. Because the internal response body is never returned to the requester, the practical impact is internal-network reconnaissance - an attacker can map which services are reachable - rather than data theft or code execution; no public exploit code has been identified at time of analysis and the issue is not a confirmed actively exploited (CISA KEV) vulnerability. The independent assessment rates this CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N, treating it as a moderate-severity reconnaissance primitive.
An authenticated user on a Nextcloud instance running the Deck app can set board-scoped configuration keys for arbitrary board IDs via the Deck config API, because the endpoint does not verify that the caller owns or has manage permission on the referenced board. Only Deck 1.16.0 through 1.18.0 are affected, and the impact is confined to configuration integrity of the targeted board - there is no data disclosure or availability loss - making this a low-to-moderate priority authorization flaw rather than a high-urgency issue. Exploitation requires a valid account on the instance (the assessed vector is PR:L, i.e. authenticated, with no user interaction), and the attacker must know or enumerate target board IDs; no public exploit code has been identified at time of analysis.
Approval bypass in the Nextcloud Approval app allows an authenticated user holding approve/reject privileges - or an attacker positioned to intercept and modify that approver's outbound approve/reject HTTP request - to approve or reject a file version whose contents changed after the approver reviewed it, simply by omitting or blanking the etag parameter. The backend only applied its etag freshness check when the parameter was present and non-empty, so the review-integrity control is skippable; impact is limited to integrity of the approval decision (CVSS 4.3, PR:L, no confidentiality or availability effect). No public exploit code was identified at time of analysis, and this is assessed as a genuinely low-priority issue whose signals are consistent.
Authorization bypass in the Nextcloud team folders app (formerly group folders), when used together with the workspace app, allows authenticated delegated administrators to reach folders outside the scope they were granted. Affected are Nextcloud deployments where organizations delegate limited team-folder administration strictly through API/REST; the attacker must already hold advanced permissions on at least some folders (CVSS 3.1 AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N, score 6.5), so unauthenticated users and ordinary accounts cannot exploit it. Confidentiality and integrity of folders outside the delegated scope are both compromised, availability is not affected, and no public exploit code has been identified at time of analysis - the CVE is not listed in CISA KEV, and the report originates from HackerOne (report 3674940).
Cross-user lock manipulation in the Nextcloud Files Lock (files_lock) app allows any authenticated user to lock or unlock files they do not own by supplying the absolute WebDAV path of another user's file, because the DAV plugin resolves the request URI without confirming that the path belongs to the session user. An attacker who can enumerate or guess a victim's path can block editor saves and PUT/MOVE/DELETE writes, and can also have the application hand back the victim's lock token, which enables removal of token-based client locks. Rated 6.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L) in the authoritative assessment, it requires a valid account and an enabled files_lock app on a multi-user instance; impact is limited to denial-of-write and lock-token disclosure with no file content read/write or code execution, and no public exploit code or confirmed active exploitation was identified at time of analysis.
Stored cross-site scripting in Shopware's media manager allows any authenticated admin to upload an unsanitized SVG file containing arbitrary JavaScript that executes in the Shopware domain context when the file is accessed by any user. The upload pipeline - spanning MediaUploadController, FileSaver, and TypeDetector - classifies SVG as a valid ImageType with VECTOR_GRAPHIC flag but performs zero content sanitization: no DOMPurify, no enshrined/svg-sanitize, no strip_tags on SVG XML content. In an e-commerce context this enables admin account takeover, customer data exfiltration, and malicious plugin installation. No public exploit identified at time of analysis and this vulnerability is not listed in CISA KEV.
Comment authorization bypass in Nextcloud Server 31.x and 32.x allows authenticated low-privilege users to read all file comments system-wide, bypassing file-level access controls. Affected are Nextcloud Server 31.0.0-31.0.11 and 32.0.0-32.0.2, plus a broad range of Nextcloud Enterprise Server branches. No public exploit has been identified at time of analysis and the vulnerability is absent from CISA KEV, but the CVSS Changed scope rating indicates sensitive organizational data embedded in comments - internal notes, credentials, review feedback - can be exposed cross-user without any file-access permission.
Two-factor authentication bypass in Nextcloud Server 32.0.0-32.0.8 and 33.0.0-33.0.2 enables a partially-authenticated attacker to access DAV endpoints (WebDAV, CalDAV, CardDAV) with full read/write privileges by reusing a pre-2FA intermediate session cookie as a Bearer token. The TEMPORARY_TOKEN issued after successful password authentication but before TOTP completion was not restricted to cookie-based requests, allowing it to be replayed in an HTTP Authorization: Bearer header against DAV APIs - entirely circumventing mandatory two-factor authentication enforcement. No public exploit has been identified at time of analysis, though a HackerOne report (3573399) documents the issue; vendor-confirmed patches are available.
Two-factor authentication bypass in Nextcloud Server 32.0.0-32.0.8 and 33.0.0-33.0.2 allows an authenticated attacker who possesses a valid user password to fully circumvent 2FA protections and gain unauthorized account access. During the login sequence, Nextcloud creates a temporary session token after credential validation but before the second factor is enforced; this token was not restricted from use in HTTP Basic Authentication or Bearer-header flows, enabling replay to authenticated API endpoints and effectively nullifying the 2FA control. Vendor-released patches exist as 32.0.9 and 33.0.3; no public exploit identified at time of analysis, though the fix PR makes the exploit mechanism technically transparent.
Nextcloud Tables versions 0.8.0 through 1.0.3 improperly disclose view filter criteria to authenticated users holding only read-only permissions on a shared view. The flaw in ViewService.php attempted to sanitize filter arrays for low-privileged users but instead exposed the full filter rules - potentially revealing sensitive column names, threshold values, or data organization logic the view owner intended to keep confidential. No public exploit code has been identified at time of analysis, and this CVE is not listed in CISA KEV, indicating no confirmed active exploitation.
Broken share revocation in Nextcloud Forms versions 4.3.0 through 5.2.7 leaves former collaborators with persistent read access to uploaded respondent files after removal. The vulnerability stems from a two-layer share architecture where removing a collaborator deleted the Forms-layer share record but silently preserved the underlying Nextcloud Files-layer share on the uploaded files folder - meaning removed users retained filesystem-level access to sensitive form submission files. No public exploit has been identified at time of analysis and the issue is not listed in CISA KEV, but the low-complexity network vector (CVSS AV:N/AC:L/PR:N/UI:N) means a removed collaborator can exploit this passively without any additional action.
User enumeration via Nextcloud Calendar's attendee suggestion endpoint affects authenticated users on versions 5.5.13-5.5.16 and 6.2.0-6.2.2. The `searchAttendee` controller method in `ContactController.php` called the contacts manager search API without passing the instance's configured sharing restriction parameters - meaning enumeration-limiting settings (`shareapi_allow_share_dialog_user_enumeration`, `shareapi_only_share_with_group_members`, group-scoped restrictions) enforced on all other sharing endpoints were silently bypassed here. An authenticated low-privilege attacker can probe the endpoint with partial name or email strings to reconstruct the full user directory, disclosing usernames and email addresses that administrators had intentionally restricted. No public exploit identified at time of analysis and no confirmed active exploitation (CISA KEV not listed).
Nextcloud's Circles (Teams) sharing feature silently generates unauthenticated public access links when folders are shared with a Team containing external email-only members, links which are never surfaced in the sharing UI and cannot be revoked by the folder owner. Affected are Nextcloud versions 32.0.0-32.0.8 and 33.0.0-33.0.2 with the Circles app in use. Any party who receives or intercepts the emailed link obtains full read, write, delete, reshare, and download access to the shared folder without a Nextcloud account, and the folder owner has no visibility or revocation path through normal interfaces. No public exploit identified at time of analysis; the issue was disclosed via HackerOne.
Nextcloud Server's files_lock application failed to enforce file ownership during WebDAV DAV lock and unlock operations, allowing any authenticated low-privilege account to lock or unlock files belonging to other users by referencing their absolute WebDAV paths. Affected releases span Nextcloud Server 32.0.0-32.0.1 and 33.0.0, plus Nextcloud Enterprise Server in the 31.0.x, 32.x, and 33.x lines prior to their respective patches. Compounding the flaw, lock tokens were leaked in server error responses, enabling an attacker to silently remove token-based locks placed by legitimate sync clients - disrupting collaborative workflows without direct file access. No public exploit code or CISA KEV listing exists at time of analysis.
Nextcloud Server's link share attachment access bypasses password protection and download restrictions for authenticated users who possess a valid share token. Affecting versions 32.0.0-32.0.9 and 33.0.0-33.0.3 of Nextcloud Server (with broader version ranges for Enterprise), an attacker authenticated to the Nextcloud instance can retrieve attachments from password-protected or download-restricted link shares by supplying a documentId they own alongside a known share token-circumventing the intended access controls entirely. No public exploit has been identified at time of analysis, and no CISA KEV listing exists; however, the CVSS vector (AV:N/AC:L/PR:L/UI:N) indicates straightforward network exploitation by any authenticated user.
Path traversal in Nextcloud Server 31.x and 32.x allows authenticated non-admin users to copy arbitrary server-side files into their own Nextcloud storage directory when an administrator has configured the `{lang}` placeholder in the template directory config value. The root cause is insufficient sanitization of the `forceLanguage` HTTP request parameter and the `ACCEPT_LANGUAGE` header in `lib/private/L10N/Factory.php`, which were used unsanitized in filesystem path construction. No public exploit identified at time of analysis, though a HackerOne report (3468140) exists; CVSS scores this as Medium (4.4) due to high complexity and privilege preconditions, and impact is limited to confidentiality with no code execution possible.
Open redirect in Nextcloud's user_oidc plugin (versions 6.1.0 through 8.2.1) allows attackers to craft OIDC login links that silently redirect victims to arbitrary external websites upon successful authentication. The root cause is insufficient redirect URL sanitization in LoginController.php - a single regex stripping the protocol and domain could be bypassed using protocol-relative URLs (e.g., //attacker.com), which browsers resolve as full external URLs. No public exploit has been identified at time of analysis, and this CVE is not listed in CISA KEV; however, the phishing potential via trusted login flows warrants prompt patching in user-facing Nextcloud deployments.
Information disclosure in the Nextcloud Approval app prior to version 2.7.2 allows authenticated users to enumerate whether arbitrary files are enrolled in approval workflows, regardless of their access rights to those files. The root cause (CWE-200) is a missing file-access authorization check in ApprovalService.php before workflow association queries are processed, confirmed by the patch diff in PR #356. No public exploit exists and no active exploitation is confirmed; the practical impact is limited to organizational workflow metadata leakage rather than file content exposure.
Privilege escalation in the Nextcloud Approval app (prior to version 2.7.2) allows authenticated users who lack sharing permissions to force the platform to distribute restricted files to approval workflow participants. By invoking the approval request flow with the createShares flag enabled, a user can bypass the system's file-sharing authorization controls entirely, causing files marked as non-shareable to be shared with designated approvers. No public exploit has been identified at time of analysis, but a vendor-confirmed patch and upstream PR diff are available.
Unauthorized access to form submissions in Nextcloud Forms prior to version 5.2.6 allows any authenticated user to read survey or form responses submitted by other users. The root cause is a missing authorization check in the `getSubmission` API endpoint (`ApiController.php`), which failed to verify whether the requesting user held the PERMISSION_RESULTS privilege or was the original submitter. With a CVSS score of 6.5 (Medium) and no public exploit identified at time of analysis, real-world risk is bounded by the requirement for an authenticated session, but the confidentiality impact is rated High given unrestricted access to potentially sensitive form response data.
Improper access control in Nextcloud Talk's signaling layer allows a low-privileged authenticated user to forcibly mute other participants' microphones during calls on deployments without the High-performance Backend. The vulnerability exists in SignalingController::sendMessages(), which processed 'control' type signaling messages without first validating that the target session (decodedMessage['to']) was a legitimate room participant - allowing session-targeted control commands to reach arbitrary users. No public exploit or CISA KEV listing exists at time of analysis, and real-world impact is limited to call disruption with no data exposure.
Unauthorized file injection in the Nextcloud end-to-end encryption application (versions 1.15.0-1.18.x) allows a low-privileged user possessing a valid E2EE files drop share link to write files into other E2EE-encrypted folders owned by the same share owner. The impact is strictly integrity-limited - confidentiality is unaffected and existing files cannot be read or modified - consistent with the CVSS score of 3.5 (Low). No public exploit has been identified and this vulnerability is not listed in the CISA KEV catalog; it was responsibly disclosed via HackerOne report #3304830.
Unauthorized chunking upload access in Nextcloud Server allows an authenticated share recipient to read temporary part files during another user's active file upload. Affecting versions 32.0.0-32.0.8 and 33.0.0-33.0.2, the flaw stems from the WebDAV chunking upload collection failing to restrict directory listing or GET requests on intermediate upload objects when accessed via a share token - a boundary the fix explicitly closes by blocking reads on FutureFile and UploadFile node types. No public exploit has been identified and no CISA KEV listing exists at time of analysis, but the high confidentiality impact (CVSS C:H) means sensitive in-transit file contents are fully exposed to any malicious share recipient who times access during an active upload.
Nextcloud Server's Circles app exposes a missing access control check on the member-add API endpoint, allowing an authenticated user to add an arbitrary circle - identified only by its internal ID - as a member of another circle without verifying that the requesting user has any relationship to the target circle. Affected versions span 32.0.0-32.0.6 and 33.0.0, with Enterprise editions from 29.x through 31.x also impacted. Exploitation is severely constrained by the 62^15 entropy of circle IDs, making the vulnerability practically exploitable only when an attacker has obtained a valid circle ID through a separate information-disclosure path, at which point they could track or infer circle membership relationships. No public exploit exists and this is not listed in CISA KEV.
Nextcloud Collectives versions 2.6.0 through 4.3.0 (exclusive) exposes deleted collective pages to unauthorized guests via a missing permission check in the public trash controller. Guests granted view-only access to a shared collective can bypass deletion-based access controls by directly querying trashbin endpoints, reading content that was intentionally removed. CVSS scores this at 2.6 (Low) with no public exploit identified at time of analysis and no CISA KEV listing, placing real-world priority at the lower end of the risk spectrum.
PIN authentication bypass in the Nextcloud Files Android app (versions 33.0.0 through 33.0.x) allows a physically present attacker to circumvent the app's passcode lock screen by pressing the Android back button immediately after the host device is unlocked. The PassCodeActivity failed to intercept back-navigation events during PIN verification, granting direct file access without completing authentication. No public exploit identified at time of analysis and no CISA KEV listing; risk is tightly constrained by the physical access vector. Patched in version 33.1.0 via upstream PR #16896.
Rename permission bypass in Nextcloud's team folder (groupfolders) feature allows authenticated low-privileged users holding READ and CREATE permissions to rename files in team folders even when UPDATE permission is explicitly denied. Affecting Nextcloud versions 17.0.0 through 21.0.3, the flaw originates from a single-character bitwise operator error in ACLStorageWrapper.php - a `&` used instead of `|` when evaluating combined permission flags effectively nullifies the UPDATE permission check. No public exploit identified at time of analysis; vendor-released patches are available across all affected version branches.
Blind Server-Side Request Forgery in Nextcloud News prior to 28.3.0-beta.1 allows low-privileged authenticated users to weaponize the feed URL submission feature - available via both the web interface and API - to coerce the Nextcloud server into making outbound HTTP requests to attacker-specified internal or private IP ranges, including localhost. Response content is never relayed back to the attacker, constraining this to a reconnaissance primitive rather than a data-exfiltration channel. No public exploit has been identified at time of analysis, EPSS sits at 0.04% (12th percentile), and CISA has not listed this in KEV, collectively indicating a low-probability real-world exploitation scenario.
Brute-force attacks against OpenClaw webhook authentication allow unauthenticated remote attackers to forge Nextcloud Talk webhook events by exploiting missing rate limiting on shared secret validation. Affecting OpenClaw versions prior to 2026.3.28, attackers can repeatedly attempt authentication without throttling to compromise weak shared secrets and inject malicious webhook payloads. CVSS 9.8 critical severity reflects network-accessible attack surface requiring no authentication. No public exploit identified at time of analysis, though EPSS data not available. Vendor-released patch available via commit e403decb6e20091b5402780a7ccd2085f98aa3cd.
OpenClaw before version 2026.2.25 fails to implement durable replay state validation for Nextcloud Talk webhook events, allowing attackers to capture and replay previously valid signed webhook requests to cause duplicate processing. This affects all versions of OpenClaw prior to the patched release, and an attacker with network access can exploit this vulnerability without authentication or user interaction to trigger integrity and availability impacts such as duplicate message processing or resource exhaustion.
OpenClaw versions prior to 2026.2.25 suffer from a webhook replay vulnerability where valid signed Nextcloud Talk webhook requests lack durable replay state suppression, allowing attackers to capture and replay previously legitimate signed requests to trigger duplicate inbound message processing. This can result in message duplication, data integrity issues, and potential availability degradation. While the CVSS score of 4.8 is moderate, the attack requires no authentication and can be executed over the network with medium complexity, making it a viable attack vector for threat actors with network visibility to webhook traffic.
OPNsense 19.1 contains multiple cross-site scripting vulnerabilities in the diag_backup.php endpoint that allow attackers to inject malicious scripts through multiple parameters including GDrive_GDriveEmail, GDrive_GDriveFolderID, GDrive_GDriveBackupCount, Nextcloud_url, Nextcloud_user, Nextcloud_password, Nextcloud_password_encryption, and Nextcloud_backupdir. [CVSS 5.4 MEDIUM]
Authenticated information disclosure in Nextcloud Server 30.0.0 lets any user holding a valid account view previews of files owned by other users by manipulating the fileId parameter on the /core/preview endpoint, sidestepping sharing permissions and any prior sharing relationship with the victim. Exploitation requires authentication but no special privilege, and publicly available exploit code exists (a Gist and a Google Drive-hosted proof of concept are referenced by NVD); CISA KEV does not list this CVE, and EPSS is low at 0.27% (19th percentile), so it is a moderate-severity disclosure issue rather than a top-tier priority. Practical exposure is concentrated in multi-user and multi-tenant deployments where many accounts and many previewable files coexist; single-user instances are largely unaffected in practice.
Nextcloud Twofactor WebAuthn before 1.4.2 and 2.4.1 allows an authenticated attacker who knows a victim's high-entropy WebAuthn public key credential ID to remove that victim's registered two-factor authentication device through a missing ownership check, forcing the victim to re-register a device on next login. The attacker cannot authenticate as the victim, and the dominant limiting factor is the 80-128 character random credential ID, which is not normally exposed and makes guessing practically infeasible; the independent assessment considers this a low real-world priority despite the vendor's CVSS 4.3 rating. No public exploit is identified at time of analysis, EPSS is 0.02% (4th percentile), and no CISA KEV entry is present.
Improper permission enforcement in the Nextcloud Deck kanban app allows an authenticated user who has been granted only the board-level 'Can share' right to alter the permission flags of other recipients on that same shared board, rather than being confined to sharing actions. Only Deck versions prior to 1.14.6 (the 1.14.x line) and the 1.15.0-beta.1 pre-release through before 1.15.2 are affected, and any instance where board sharing with multiple recipients is used is exposed; exploitation requires an existing, trusted collaborator account with 'Can share' but not 'Can manage', so anonymous or unauthenticated access is not possible. The impact is rated 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N) - a limited integrity effect with no data disclosure or service disruption - and there is no public exploit identified at time of analysis, with EPSS at 0.01% (2nd percentile), making this a low-priority, genuinely low-risk issue; vendor patches are available in 1.14.6 and 1.15.2.
An authorization bypass in the Nextcloud Talk conferencing app (spreed) lets an authenticated conversation participant who holds chat permissions delete other participants' poll drafts by supplying the draft's numeric ID, because the poll controller never verified moderator or ownership rights before acting on that identifier. The flaw affects Talk versions prior to 20.1.8 and the 21.0.0-beta.1 through 21.1.2 range, and is rated CVSS 4.3 (network reachable, low privileges required, integrity-only impact) with an EPSS score of just 0.01% (2nd percentile), indicating a low-likelihood, low-priority issue. No public exploit code has been identified at the time of analysis, and CISA KEV does not list this CVE; vendor-released patches (20.1.8 and 21.1.2) are available.
Stored CSS injection in the Nextcloud Contacts app (versions prior to 5.5.4, 6.0.6, and 7.2.5) allows an authenticated user to place crafted markup in a contact's organisation or title field that is rendered unescaped when another user views that contact, enabling limited page defacement and CSS-based information leakage. Because the Nextcloud Server content security policy blocks JavaScript and other active content, the impact is confined to loading attacker-supplied stylesheets rather than arbitrary script execution, and exploitation requires the attacker to hold a valid account and the victim to open the affected contact entry. Publicly available exploit code exists, but the EPSS score is only 0.02% (5th percentile) and there is no evidence of confirmed active exploitation.
Nextcloud Tables allows you to create your own tables with individual columns. Prior to 0.8.7 and 0.9.4, authenticated users were able to view meta data of columns in other tables of the Tables app by modifying the numeric ID in a request. This vulnerability is fixed in 0.8.7 and 0.9.4.
An authenticated authorization bypass in the Nextcloud Tables app (CWE-639) lets a low-privilege user move a column from a table they created into a table owned by another user, corrupting the victim's table structure. All deployments of the Tables app below 0.8.6, and 0.9.0-beta.1 through versions before 0.9.3, are affected; the flaw requires an authenticated Nextcloud account (CVSS:3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N, base 4.3) and needs no victim interaction. Impact is limited to integrity of table definitions with no confidentiality or availability loss, EPSS is negligible at 0.02% (4th percentile) and no public exploit code was identified at time of analysis, so real-world priority is low. Vendor-released patch: 0.8.6 and 0.9.3.
Information disclosure in Nextcloud Desktop before 3.16.5 occurs when a user manually locks a file inside an end-to-end encrypted directory: the client sends the cleartext file path to the server, where an administrator can read it in logs. The exposure is limited to the path (no file contents or keys) and the CVSS vector (PR:H) confirms the attacker must already have high privileges, making this a low-severity issue (CVSS 2.7). No public exploit identified at time of analysis; EPSS is 0.03% (7th percentile).
Authenticated users with write access to a Nextcloud Deck board can spoof attachment file extensions by embedding Unicode right-to-left override (U+202E) characters in a filename, so a downloaded file is displayed with a trusted extension while its real type differs. The flaw affects Nextcloud Deck before 1.12.7, 1.14.4, and 1.15.1, and requires a second user to view the card and actively choose to download the misleadingly named attachment. Vendor patches (1.12.7, 1.14.4, 1.15.1) strip the RTLO character and render the basename and extension separately; the assessed impact is medium-severity UI spoofing with low real-world urgency, EPSS 0.01% (1st percentile), and no public exploit identified at time of analysis.
A security vulnerability in a group or team. (CVSS 3.5). Remediation should follow standard vulnerability management procedures. Vendor patch is available.
The Nextcloud Approval app allows approval or disapproval of files in the sidebar. Prior to 1.3.1 and 2.5.0, an authenticated user listed as a requester in a workflow can set another user’s file into the “pending approval” without access to the file by using the numeric file id. This vulnerability is fixed in 1.3.1 and 2.5.0.
Stored HTML injection in the Nextcloud Mail app's message list lets an authenticated user embed crafted markup into email subjects that is rendered for other mailbox users. The issue affects Nextcloud Mail prior to 5.5.3 (including 5.2.0-beta.1) and requires victim interaction, since a second user must open the Mail app and view the message list for the stored subject to render. Because the Nextcloud Server content security policy blocks JavaScript execution, impact is confined to HTML injection such as phishing, content spoofing, and UI manipulation rather than script-driven session compromise; EPSS is 0.02% (5th percentile) and no public exploit has been identified at time of analysis.
Information disclosure in Nextcloud Tables before 0.8.9, 0.9.6, and 1.0.1 lets any authenticated Nextcloud user read the sharing configuration of tables and views they do not own - which numeric table ID is shared with which users or groups and with what permissions - by calling the share-listing endpoints of the Tables API. Exploitation requires a valid Nextcloud session in an instance where the Tables app is enabled, and the exposure is limited to sharing metadata rather than the tables' contents, so there is no integrity or availability impact. The published CVSS of 5.3 (assessed as PR:L rather than the vendor's PR:N) combined with an EPSS score of only 0.02% (4th percentile) and no public exploit code identified makes this a low-to-moderate priority issue; vendor-released fixes exist in 0.8.9, 0.9.6, and 1.0.1.
A security vulnerability in Nextcloud Server and Enterprise Server (CVSS 4.3). Remediation should follow standard vulnerability management procedures. Vendor patch is available.
A security vulnerability in Nextcloud Calendar (CVSS 5.7). Risk factors: public PoC available. Vendor patch is available.
Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 31.0.1, non-privileged users can modify tags on files they should not have access to via bulk tagging. This vulnerability is fixed in 31.0.1.
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.19, 5.5.6, and 6.0.1, the calendar app allowed blindly booking appointments with a squential ID without known the appointment token. This vulnerability is fixed in 4.7.19, 5.5.6, and 6.0.1.
Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Server Enterprise prior to 31.0.12 and 32.0.3, a missing sanitization allowed malicious users to circumvent the content security policy when a malicious user manages to trick a user it viewing an uploaded SVG outside of the Nextcloud Servers web page.
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 6.0.3, the Calendar app generates participant tokens for meeting proposals using a hash function, allowing an attacker to compute valid participant tokens, which allowed them to request details and submit dates in meeting proposals. The tokens are not purely random generated. This vulnerability is fixed in 6.0.3.
A security vulnerability in Nextcloud Server (CVSS 4.5) that allows an authenticated user. Remediation should follow standard vulnerability management procedures. Vendor patch is available.
Cross-site scripting (XSS) vulnerability in a reachable files_pdfviewer example directory in Nextcloud with versions before 22.2.10.33, 23.0.12.29, 24.0.12.28, 25.0.13.23, 26.0.13.20, 27.1.11.20, 28.0.14.11, 29.0.16.8, 30.0.17, 31.0.10, and 32.0.1...
Collabora Online - Built-in CODE Server (richdocumentscode) provides a built-in server with all of the document editing features of Collabora Online. In versions prior to 25.04.702, Collabora Online has a Configuration-Dependent RCE (OS Command Injection) in richdocumentscode proxy. Users of Nextcloud with Collabora Online - Built-in CODE Server app can be vulnerable to attack via proxy.php and an intermediate reverse proxy. This vulnerability is fixed in 25.04.702.
Authenticated information disclosure in the Nextcloud Tables app (versions before 0.7.6, 0.8.8, and 0.9.5) lets a logged-in user trick the table-import flow into reading arbitrary files from the server. By invoking the import or preview import endpoint (ImportService.php) with a server-side path instead of an actual uploaded file, the attacker receives the parsed contents of any file whose format the bundled PhpSpreadsheet library can read, such as spreadsheets, CSV, ODS, or XML - resulting in high confidentiality impact with no integrity or availability effect (CVSS 3.1: 6.5, AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N). No public exploit code has been identified at time of analysis and the flaw is not listed as confirmed actively exploited (CISA KEV); EPSS is low at roughly 0.53% (43rd percentile), reflecting the authenticated precondition and the fact that the leak is confined to PhpSpreadsheet-parseable formats. This is a moderate-risk authenticated information disclosure flaw, not a top-tier priority.
Nextcloud Server is a self hosted personal cloud system. Rated low severity (CVSS 2.6), this vulnerability is remotely exploitable. No vendor patch available.
Nextcloud Server is a self hosted personal cloud system, and the Nextcloud Groupfolders app provides admin-configured folders shared by everyone in a group or team. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. This Allocation of Resources Without Limits vulnerability could allow attackers to exhaust system resources through uncontrolled allocation.
Nextcloud Desktop is the desktop sync client for Nextcloud. Rated medium severity (CVSS 5.0).
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 4.3), this vulnerability is no authentication required, low attack complexity. This Server-Side Request Forgery (SSRF) vulnerability could allow attackers to make the server perform requests to unintended internal or external resources.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 6.4), this vulnerability is remotely exploitable. No vendor patch available.
Nextcloud Server is a self hosted personal cloud system. Rated low severity (CVSS 3.5), this vulnerability is remotely exploitable, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
user_oidc app is an OpenID Connect user backend for Nextcloud. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Open Redirect vulnerability could allow attackers to redirect users to malicious websites via URL manipulation.
Nextcloud Tables allows users to to create tables with individual columns. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity.
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Rated medium severity (CVSS 5.7), this vulnerability is remotely exploitable, low attack complexity.
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
Nextcloud Tables allows users to to create tables with individual columns. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Uncontrolled Resource Consumption vulnerability could allow attackers to cause denial of service by exhausting system resources.
Nextcloud Server is a self hosted personal cloud system. Rated high severity (CVSS 8.2), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no authentication required. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
Unauthenticated OS command injection in the Collabora Online Built-in CODE Server Nextcloud app (richdocumentscode) before 26.4.303 allows remote attackers to execute arbitrary commands on the Nextcloud host via proxy.php, but only while the bundled CODE server process is not running - the window right after a restart, during startup, or following a crash. The CVSS 4.0 score is 9.2 and the CVE record attributes exploitation during September and October 2026, making this a genuine high-priority issue rather than a paper-tiger high-severity finding; the practical barrier is timing, not authentication, since the CVSS vectors carry PR:N/UI:N and an attacker can simply poll the endpoint until CODE is down. Standalone Collabora Online servers do not ship proxy.php and are explicitly not affected - the exposure is confined to Nextcloud instances with the richdocumentscode app, and the flaw is distinct from CVE-2025-66208.
Unauthenticated vector-store tampering in Nextcloud MCP Server before 0.117.2 lets any network attacker who can reach the /webhooks/nextcloud endpoint delete or force re-indexing of Qdrant semantic-search embeddings for arbitrary users. Because WEBHOOK_SECRET defaults to None and startup never enforces it, the webhook receiver processes forged POSTs and trusts the attacker-supplied user.uid, so looping over document IDs can wipe the entire search index for all users. A working proof-of-concept is published in the GHSA advisory; publicly available exploit code exists, though there is no public exploit identified in CISA KEV.
Cross-project folder hijacking in OpenProject before 17.3.3 and 17.4.1 lets a project-admin abuse an insecure direct object reference (CWE-639) to take over another project's managed Nextcloud or OneDrive storage folder. By PATCHing the storages_project_storage[project_folder_id] parameter on /projects/<id>/settings/project_storages/<ps_id>, an attacker writes a victim project's folder ID into their own ProjectStorage row, and the next managed-folder sync rewrites the target folder's ACL to the attacker's project member list. CVSS is 9.9 and the issue carries a scope change, but there is no public exploit identified at time of analysis and it is not on CISA KEV.
Blind SQL injection in the Nextcloud Tables app affects versions 0.9.0 through 0.9.6 and 1.0.0 through 1.0.1, allowing authenticated users with access to the Tables app to inject SQL into the ORDER BY clause of database queries. The flaw permits bit-by-bit data extraction or time-based exfiltration against the underlying database, and no public exploit identified at time of analysis. Patches are available in versions 0.9.7 and 1.0.2.
SQL injection in the Nextcloud Tables app allows authenticated users with access to the Tables feature to execute arbitrary SQL queries against the backend database via a stored injection vector. Although a 20-byte length limit is imposed on the injected payload, carefully crafted input can break out of this restriction, enabling data extraction and modification. No public exploit identified at time of analysis, and the issue is not listed in CISA KEV.
Authentication bypass in the Nextcloud user_oidc app (versions 1.3.6 up to but not including 8.4.0) lets users that were originally provisioned via LDAP continue to authenticate through OpenID Connect even after their account has been deleted. Because an internal LDAP-enabled check was inverted, deletion did not correctly revoke OIDC login for affected accounts, meaning a de-provisioned user with valid OIDC credentials could regain access to the platform. There is no public exploit identified at time of analysis and EPSS is very low (0.03%), but the flaw is a genuine access-control gap fixed in version 8.4.0.
Improper authorization in the Nextcloud Server CalDAV backend allows an authenticated user who knows another user's principal URL to gain full read/write access to that user's calendar in versions 32.0.0 to before 32.0.9 and 33.0.0 to before 33.0.3. The flaw was reported via HackerOne (report 3545964) and patched in PR 59962 by introducing dedicated ProxyRead/ProxyWrite ACL-aware classes; no public exploit identified at time of analysis and the issue is not listed in CISA KEV.
Authentication bypass in Nextcloud's User OIDC app (versions 0.3.0-3.0.x, 5.0.0-5.0.x, and 6.0.0-6.3.x) allows a malicious ID4me authority to impersonate arbitrary users due to missing JWT signature verification in the ID4me login flow. The flaw stems from a literal 'TODO: VALIATE SIGNATURE!' code comment that left ID tokens accepted without cryptographic validation, enabling identity spoofing once a victim is redirected through the attacker-controlled authority. No public exploit identified at time of analysis, and the issue is not listed in CISA KEV.
Authorization bypass in Windmill 1.56.0-1.614.0 enables Operator role users to escalate privileges to remote code execution. Operators can bypass documented role restrictions via unprotected backend API endpoints to create/modify scripts, flows, and apps, then execute arbitrary code through the jobs API. Public exploit code exists (GitHub: Chocapikk/Windfall). EPSS data unavailable, but the low attack complexity (AC:L), network access vector (AV:N), and availability of weaponized POC indicate elevated real-world risk for self-hosted Windmill deployments with Operator-level users.
Authentication bypass in OpenClaw's Nextcloud Talk plugin versions ≤2026.2.2 allows remote unauthenticated attackers to bypass DM and room allowlists by spoofing display names. Attackers can change their Nextcloud display name to match an allowlisted user ID, gaining unauthorized access to restricted conversations without authentication. EPSS score is low (0.05%, 16th percentile), indicating low observed exploitation probability. No active exploitation confirmed; vulnerability was responsibly disclosed by AISLE Research Team and patched in version 2026.2.6.
Nextcloud server is an open source home cloud implementation. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. This OS Command Injection vulnerability could allow attackers to execute arbitrary operating system commands on the host.
File owners on Nextcloud Server cannot release TYPE_TOKEN file locks that other users have placed on their files, leaving the file locked with no in-product recovery path; administrators currently have to clear the orphaned lock directly in the database. The defect is an access-control gap (CWE-284) reachable over the network by any authenticated user who can acquire a token lock, typically in shared-folder or multi-user collaboration scenarios, and it is availability-only - no confidentiality or integrity impact - as reflected in the assessed vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. No public exploit code has been identified and there is no evidence of active exploitation, so despite a 6.5 base score this behaves as an accidental or malicious file-lockout rather than a scalable remote attack.
Persistent sidebar layout manipulation in the Nextcloud Collectives app allows an authenticated user with page-edit permission to submit oversized text containing line breaks to the page emoji update endpoint, which accepts the value without length or character validation. When another user subsequently views the affected collective page, the unvalidated emoji string overflows and breaks the rendered sidebar, hiding other navigation items from view. The impact is confined to client-side layout integrity with no confidentiality or availability loss (CVSS 3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N, published vector 2.4 with PR:H), making this a genuinely low-risk issue; no public exploit code has been identified at time of analysis, and it applies only where the optional Collectives app is installed.
Authorization bypass in Nextcloud Server (Circles feature) lets an authenticated user retrieve the membership list of a circle they do not belong to, exposing membership information for Nextcloud Server 32.0.0 through 34.0.0, as detailed in HackerOne report 3484601. Exploitation is gated by a severe practical constraint: the attacker must supply an existing circle's unique identifier, which lives in a 62^15-space (roughly 90-bit) keyspace, so the CVSS 3.1 score reflects high attack complexity rather than an easily reachable bypass and no public exploit has been identified at time of analysis. Impact is limited to confidentiality of one circle's member list; no modification, deletion, or service disruption is possible, making this a low-priority issue for most deployments.
Metadata disclosure in Nextcloud Server's Photos app smart albums allows an authenticated user to enumerate file names, IDs, and other metadata from a sharer's folders that were never intended to be included in the shared album. This moderate, tightly scoped authorization flaw (CWE-284) occurs because the smart album builds its file listing using the viewing user's photosSourceFolders search configuration instead of the album owner's configuration; an attacker who has been granted a filter-based smart album share can modify their own folder settings to widen the search scope. No public exploit code is identified at time of analysis, and the independent assessment limits impact to metadata (not file content) within the filter-reachable scope; it cannot reach files of users who have not shared such an album.
Blind server-side request forgery in the Nextcloud Circles (Teams) app lets any unauthenticated remote user force the Nextcloud Server to issue an outbound GET request to an attacker-chosen internal or private address through the public endpoints POST /apps/circles/event/ and POST /apps/circles/incoming/. The flaw sits in remote-instance signature verification, which fetches the attacker-supplied keyId URL before trust in the remote instance is established and explicitly permits local and private address ranges, bypassing Nextcloud's core SSRF protections. Because the internal response body is never returned to the requester, the practical impact is internal-network reconnaissance - an attacker can map which services are reachable - rather than data theft or code execution; no public exploit code has been identified at time of analysis and the issue is not a confirmed actively exploited (CISA KEV) vulnerability. The independent assessment rates this CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N, treating it as a moderate-severity reconnaissance primitive.
An authenticated user on a Nextcloud instance running the Deck app can set board-scoped configuration keys for arbitrary board IDs via the Deck config API, because the endpoint does not verify that the caller owns or has manage permission on the referenced board. Only Deck 1.16.0 through 1.18.0 are affected, and the impact is confined to configuration integrity of the targeted board - there is no data disclosure or availability loss - making this a low-to-moderate priority authorization flaw rather than a high-urgency issue. Exploitation requires a valid account on the instance (the assessed vector is PR:L, i.e. authenticated, with no user interaction), and the attacker must know or enumerate target board IDs; no public exploit code has been identified at time of analysis.
Approval bypass in the Nextcloud Approval app allows an authenticated user holding approve/reject privileges - or an attacker positioned to intercept and modify that approver's outbound approve/reject HTTP request - to approve or reject a file version whose contents changed after the approver reviewed it, simply by omitting or blanking the etag parameter. The backend only applied its etag freshness check when the parameter was present and non-empty, so the review-integrity control is skippable; impact is limited to integrity of the approval decision (CVSS 4.3, PR:L, no confidentiality or availability effect). No public exploit code was identified at time of analysis, and this is assessed as a genuinely low-priority issue whose signals are consistent.
Authorization bypass in the Nextcloud team folders app (formerly group folders), when used together with the workspace app, allows authenticated delegated administrators to reach folders outside the scope they were granted. Affected are Nextcloud deployments where organizations delegate limited team-folder administration strictly through API/REST; the attacker must already hold advanced permissions on at least some folders (CVSS 3.1 AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N, score 6.5), so unauthenticated users and ordinary accounts cannot exploit it. Confidentiality and integrity of folders outside the delegated scope are both compromised, availability is not affected, and no public exploit code has been identified at time of analysis - the CVE is not listed in CISA KEV, and the report originates from HackerOne (report 3674940).
Cross-user lock manipulation in the Nextcloud Files Lock (files_lock) app allows any authenticated user to lock or unlock files they do not own by supplying the absolute WebDAV path of another user's file, because the DAV plugin resolves the request URI without confirming that the path belongs to the session user. An attacker who can enumerate or guess a victim's path can block editor saves and PUT/MOVE/DELETE writes, and can also have the application hand back the victim's lock token, which enables removal of token-based client locks. Rated 6.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L) in the authoritative assessment, it requires a valid account and an enabled files_lock app on a multi-user instance; impact is limited to denial-of-write and lock-token disclosure with no file content read/write or code execution, and no public exploit code or confirmed active exploitation was identified at time of analysis.
Stored cross-site scripting in Shopware's media manager allows any authenticated admin to upload an unsanitized SVG file containing arbitrary JavaScript that executes in the Shopware domain context when the file is accessed by any user. The upload pipeline - spanning MediaUploadController, FileSaver, and TypeDetector - classifies SVG as a valid ImageType with VECTOR_GRAPHIC flag but performs zero content sanitization: no DOMPurify, no enshrined/svg-sanitize, no strip_tags on SVG XML content. In an e-commerce context this enables admin account takeover, customer data exfiltration, and malicious plugin installation. No public exploit identified at time of analysis and this vulnerability is not listed in CISA KEV.
Comment authorization bypass in Nextcloud Server 31.x and 32.x allows authenticated low-privilege users to read all file comments system-wide, bypassing file-level access controls. Affected are Nextcloud Server 31.0.0-31.0.11 and 32.0.0-32.0.2, plus a broad range of Nextcloud Enterprise Server branches. No public exploit has been identified at time of analysis and the vulnerability is absent from CISA KEV, but the CVSS Changed scope rating indicates sensitive organizational data embedded in comments - internal notes, credentials, review feedback - can be exposed cross-user without any file-access permission.
Two-factor authentication bypass in Nextcloud Server 32.0.0-32.0.8 and 33.0.0-33.0.2 enables a partially-authenticated attacker to access DAV endpoints (WebDAV, CalDAV, CardDAV) with full read/write privileges by reusing a pre-2FA intermediate session cookie as a Bearer token. The TEMPORARY_TOKEN issued after successful password authentication but before TOTP completion was not restricted to cookie-based requests, allowing it to be replayed in an HTTP Authorization: Bearer header against DAV APIs - entirely circumventing mandatory two-factor authentication enforcement. No public exploit has been identified at time of analysis, though a HackerOne report (3573399) documents the issue; vendor-confirmed patches are available.
Two-factor authentication bypass in Nextcloud Server 32.0.0-32.0.8 and 33.0.0-33.0.2 allows an authenticated attacker who possesses a valid user password to fully circumvent 2FA protections and gain unauthorized account access. During the login sequence, Nextcloud creates a temporary session token after credential validation but before the second factor is enforced; this token was not restricted from use in HTTP Basic Authentication or Bearer-header flows, enabling replay to authenticated API endpoints and effectively nullifying the 2FA control. Vendor-released patches exist as 32.0.9 and 33.0.3; no public exploit identified at time of analysis, though the fix PR makes the exploit mechanism technically transparent.
Nextcloud Tables versions 0.8.0 through 1.0.3 improperly disclose view filter criteria to authenticated users holding only read-only permissions on a shared view. The flaw in ViewService.php attempted to sanitize filter arrays for low-privileged users but instead exposed the full filter rules - potentially revealing sensitive column names, threshold values, or data organization logic the view owner intended to keep confidential. No public exploit code has been identified at time of analysis, and this CVE is not listed in CISA KEV, indicating no confirmed active exploitation.
Broken share revocation in Nextcloud Forms versions 4.3.0 through 5.2.7 leaves former collaborators with persistent read access to uploaded respondent files after removal. The vulnerability stems from a two-layer share architecture where removing a collaborator deleted the Forms-layer share record but silently preserved the underlying Nextcloud Files-layer share on the uploaded files folder - meaning removed users retained filesystem-level access to sensitive form submission files. No public exploit has been identified at time of analysis and the issue is not listed in CISA KEV, but the low-complexity network vector (CVSS AV:N/AC:L/PR:N/UI:N) means a removed collaborator can exploit this passively without any additional action.
User enumeration via Nextcloud Calendar's attendee suggestion endpoint affects authenticated users on versions 5.5.13-5.5.16 and 6.2.0-6.2.2. The `searchAttendee` controller method in `ContactController.php` called the contacts manager search API without passing the instance's configured sharing restriction parameters - meaning enumeration-limiting settings (`shareapi_allow_share_dialog_user_enumeration`, `shareapi_only_share_with_group_members`, group-scoped restrictions) enforced on all other sharing endpoints were silently bypassed here. An authenticated low-privilege attacker can probe the endpoint with partial name or email strings to reconstruct the full user directory, disclosing usernames and email addresses that administrators had intentionally restricted. No public exploit identified at time of analysis and no confirmed active exploitation (CISA KEV not listed).
Nextcloud's Circles (Teams) sharing feature silently generates unauthenticated public access links when folders are shared with a Team containing external email-only members, links which are never surfaced in the sharing UI and cannot be revoked by the folder owner. Affected are Nextcloud versions 32.0.0-32.0.8 and 33.0.0-33.0.2 with the Circles app in use. Any party who receives or intercepts the emailed link obtains full read, write, delete, reshare, and download access to the shared folder without a Nextcloud account, and the folder owner has no visibility or revocation path through normal interfaces. No public exploit identified at time of analysis; the issue was disclosed via HackerOne.
Nextcloud Server's files_lock application failed to enforce file ownership during WebDAV DAV lock and unlock operations, allowing any authenticated low-privilege account to lock or unlock files belonging to other users by referencing their absolute WebDAV paths. Affected releases span Nextcloud Server 32.0.0-32.0.1 and 33.0.0, plus Nextcloud Enterprise Server in the 31.0.x, 32.x, and 33.x lines prior to their respective patches. Compounding the flaw, lock tokens were leaked in server error responses, enabling an attacker to silently remove token-based locks placed by legitimate sync clients - disrupting collaborative workflows without direct file access. No public exploit code or CISA KEV listing exists at time of analysis.
Nextcloud Server's link share attachment access bypasses password protection and download restrictions for authenticated users who possess a valid share token. Affecting versions 32.0.0-32.0.9 and 33.0.0-33.0.3 of Nextcloud Server (with broader version ranges for Enterprise), an attacker authenticated to the Nextcloud instance can retrieve attachments from password-protected or download-restricted link shares by supplying a documentId they own alongside a known share token-circumventing the intended access controls entirely. No public exploit has been identified at time of analysis, and no CISA KEV listing exists; however, the CVSS vector (AV:N/AC:L/PR:L/UI:N) indicates straightforward network exploitation by any authenticated user.
Path traversal in Nextcloud Server 31.x and 32.x allows authenticated non-admin users to copy arbitrary server-side files into their own Nextcloud storage directory when an administrator has configured the `{lang}` placeholder in the template directory config value. The root cause is insufficient sanitization of the `forceLanguage` HTTP request parameter and the `ACCEPT_LANGUAGE` header in `lib/private/L10N/Factory.php`, which were used unsanitized in filesystem path construction. No public exploit identified at time of analysis, though a HackerOne report (3468140) exists; CVSS scores this as Medium (4.4) due to high complexity and privilege preconditions, and impact is limited to confidentiality with no code execution possible.
Open redirect in Nextcloud's user_oidc plugin (versions 6.1.0 through 8.2.1) allows attackers to craft OIDC login links that silently redirect victims to arbitrary external websites upon successful authentication. The root cause is insufficient redirect URL sanitization in LoginController.php - a single regex stripping the protocol and domain could be bypassed using protocol-relative URLs (e.g., //attacker.com), which browsers resolve as full external URLs. No public exploit has been identified at time of analysis, and this CVE is not listed in CISA KEV; however, the phishing potential via trusted login flows warrants prompt patching in user-facing Nextcloud deployments.
Information disclosure in the Nextcloud Approval app prior to version 2.7.2 allows authenticated users to enumerate whether arbitrary files are enrolled in approval workflows, regardless of their access rights to those files. The root cause (CWE-200) is a missing file-access authorization check in ApprovalService.php before workflow association queries are processed, confirmed by the patch diff in PR #356. No public exploit exists and no active exploitation is confirmed; the practical impact is limited to organizational workflow metadata leakage rather than file content exposure.
Privilege escalation in the Nextcloud Approval app (prior to version 2.7.2) allows authenticated users who lack sharing permissions to force the platform to distribute restricted files to approval workflow participants. By invoking the approval request flow with the createShares flag enabled, a user can bypass the system's file-sharing authorization controls entirely, causing files marked as non-shareable to be shared with designated approvers. No public exploit has been identified at time of analysis, but a vendor-confirmed patch and upstream PR diff are available.
Unauthorized access to form submissions in Nextcloud Forms prior to version 5.2.6 allows any authenticated user to read survey or form responses submitted by other users. The root cause is a missing authorization check in the `getSubmission` API endpoint (`ApiController.php`), which failed to verify whether the requesting user held the PERMISSION_RESULTS privilege or was the original submitter. With a CVSS score of 6.5 (Medium) and no public exploit identified at time of analysis, real-world risk is bounded by the requirement for an authenticated session, but the confidentiality impact is rated High given unrestricted access to potentially sensitive form response data.
Improper access control in Nextcloud Talk's signaling layer allows a low-privileged authenticated user to forcibly mute other participants' microphones during calls on deployments without the High-performance Backend. The vulnerability exists in SignalingController::sendMessages(), which processed 'control' type signaling messages without first validating that the target session (decodedMessage['to']) was a legitimate room participant - allowing session-targeted control commands to reach arbitrary users. No public exploit or CISA KEV listing exists at time of analysis, and real-world impact is limited to call disruption with no data exposure.
Unauthorized file injection in the Nextcloud end-to-end encryption application (versions 1.15.0-1.18.x) allows a low-privileged user possessing a valid E2EE files drop share link to write files into other E2EE-encrypted folders owned by the same share owner. The impact is strictly integrity-limited - confidentiality is unaffected and existing files cannot be read or modified - consistent with the CVSS score of 3.5 (Low). No public exploit has been identified and this vulnerability is not listed in the CISA KEV catalog; it was responsibly disclosed via HackerOne report #3304830.
Unauthorized chunking upload access in Nextcloud Server allows an authenticated share recipient to read temporary part files during another user's active file upload. Affecting versions 32.0.0-32.0.8 and 33.0.0-33.0.2, the flaw stems from the WebDAV chunking upload collection failing to restrict directory listing or GET requests on intermediate upload objects when accessed via a share token - a boundary the fix explicitly closes by blocking reads on FutureFile and UploadFile node types. No public exploit has been identified and no CISA KEV listing exists at time of analysis, but the high confidentiality impact (CVSS C:H) means sensitive in-transit file contents are fully exposed to any malicious share recipient who times access during an active upload.
Nextcloud Server's Circles app exposes a missing access control check on the member-add API endpoint, allowing an authenticated user to add an arbitrary circle - identified only by its internal ID - as a member of another circle without verifying that the requesting user has any relationship to the target circle. Affected versions span 32.0.0-32.0.6 and 33.0.0, with Enterprise editions from 29.x through 31.x also impacted. Exploitation is severely constrained by the 62^15 entropy of circle IDs, making the vulnerability practically exploitable only when an attacker has obtained a valid circle ID through a separate information-disclosure path, at which point they could track or infer circle membership relationships. No public exploit exists and this is not listed in CISA KEV.
Nextcloud Collectives versions 2.6.0 through 4.3.0 (exclusive) exposes deleted collective pages to unauthorized guests via a missing permission check in the public trash controller. Guests granted view-only access to a shared collective can bypass deletion-based access controls by directly querying trashbin endpoints, reading content that was intentionally removed. CVSS scores this at 2.6 (Low) with no public exploit identified at time of analysis and no CISA KEV listing, placing real-world priority at the lower end of the risk spectrum.
PIN authentication bypass in the Nextcloud Files Android app (versions 33.0.0 through 33.0.x) allows a physically present attacker to circumvent the app's passcode lock screen by pressing the Android back button immediately after the host device is unlocked. The PassCodeActivity failed to intercept back-navigation events during PIN verification, granting direct file access without completing authentication. No public exploit identified at time of analysis and no CISA KEV listing; risk is tightly constrained by the physical access vector. Patched in version 33.1.0 via upstream PR #16896.
Rename permission bypass in Nextcloud's team folder (groupfolders) feature allows authenticated low-privileged users holding READ and CREATE permissions to rename files in team folders even when UPDATE permission is explicitly denied. Affecting Nextcloud versions 17.0.0 through 21.0.3, the flaw originates from a single-character bitwise operator error in ACLStorageWrapper.php - a `&` used instead of `|` when evaluating combined permission flags effectively nullifies the UPDATE permission check. No public exploit identified at time of analysis; vendor-released patches are available across all affected version branches.
Blind Server-Side Request Forgery in Nextcloud News prior to 28.3.0-beta.1 allows low-privileged authenticated users to weaponize the feed URL submission feature - available via both the web interface and API - to coerce the Nextcloud server into making outbound HTTP requests to attacker-specified internal or private IP ranges, including localhost. Response content is never relayed back to the attacker, constraining this to a reconnaissance primitive rather than a data-exfiltration channel. No public exploit has been identified at time of analysis, EPSS sits at 0.04% (12th percentile), and CISA has not listed this in KEV, collectively indicating a low-probability real-world exploitation scenario.
Brute-force attacks against OpenClaw webhook authentication allow unauthenticated remote attackers to forge Nextcloud Talk webhook events by exploiting missing rate limiting on shared secret validation. Affecting OpenClaw versions prior to 2026.3.28, attackers can repeatedly attempt authentication without throttling to compromise weak shared secrets and inject malicious webhook payloads. CVSS 9.8 critical severity reflects network-accessible attack surface requiring no authentication. No public exploit identified at time of analysis, though EPSS data not available. Vendor-released patch available via commit e403decb6e20091b5402780a7ccd2085f98aa3cd.
OpenClaw before version 2026.2.25 fails to implement durable replay state validation for Nextcloud Talk webhook events, allowing attackers to capture and replay previously valid signed webhook requests to cause duplicate processing. This affects all versions of OpenClaw prior to the patched release, and an attacker with network access can exploit this vulnerability without authentication or user interaction to trigger integrity and availability impacts such as duplicate message processing or resource exhaustion.
OpenClaw versions prior to 2026.2.25 suffer from a webhook replay vulnerability where valid signed Nextcloud Talk webhook requests lack durable replay state suppression, allowing attackers to capture and replay previously legitimate signed requests to trigger duplicate inbound message processing. This can result in message duplication, data integrity issues, and potential availability degradation. While the CVSS score of 4.8 is moderate, the attack requires no authentication and can be executed over the network with medium complexity, making it a viable attack vector for threat actors with network visibility to webhook traffic.
OPNsense 19.1 contains multiple cross-site scripting vulnerabilities in the diag_backup.php endpoint that allow attackers to inject malicious scripts through multiple parameters including GDrive_GDriveEmail, GDrive_GDriveFolderID, GDrive_GDriveBackupCount, Nextcloud_url, Nextcloud_user, Nextcloud_password, Nextcloud_password_encryption, and Nextcloud_backupdir. [CVSS 5.4 MEDIUM]
Authenticated information disclosure in Nextcloud Server 30.0.0 lets any user holding a valid account view previews of files owned by other users by manipulating the fileId parameter on the /core/preview endpoint, sidestepping sharing permissions and any prior sharing relationship with the victim. Exploitation requires authentication but no special privilege, and publicly available exploit code exists (a Gist and a Google Drive-hosted proof of concept are referenced by NVD); CISA KEV does not list this CVE, and EPSS is low at 0.27% (19th percentile), so it is a moderate-severity disclosure issue rather than a top-tier priority. Practical exposure is concentrated in multi-user and multi-tenant deployments where many accounts and many previewable files coexist; single-user instances are largely unaffected in practice.
Nextcloud Twofactor WebAuthn before 1.4.2 and 2.4.1 allows an authenticated attacker who knows a victim's high-entropy WebAuthn public key credential ID to remove that victim's registered two-factor authentication device through a missing ownership check, forcing the victim to re-register a device on next login. The attacker cannot authenticate as the victim, and the dominant limiting factor is the 80-128 character random credential ID, which is not normally exposed and makes guessing practically infeasible; the independent assessment considers this a low real-world priority despite the vendor's CVSS 4.3 rating. No public exploit is identified at time of analysis, EPSS is 0.02% (4th percentile), and no CISA KEV entry is present.
Improper permission enforcement in the Nextcloud Deck kanban app allows an authenticated user who has been granted only the board-level 'Can share' right to alter the permission flags of other recipients on that same shared board, rather than being confined to sharing actions. Only Deck versions prior to 1.14.6 (the 1.14.x line) and the 1.15.0-beta.1 pre-release through before 1.15.2 are affected, and any instance where board sharing with multiple recipients is used is exposed; exploitation requires an existing, trusted collaborator account with 'Can share' but not 'Can manage', so anonymous or unauthenticated access is not possible. The impact is rated 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N) - a limited integrity effect with no data disclosure or service disruption - and there is no public exploit identified at time of analysis, with EPSS at 0.01% (2nd percentile), making this a low-priority, genuinely low-risk issue; vendor patches are available in 1.14.6 and 1.15.2.
An authorization bypass in the Nextcloud Talk conferencing app (spreed) lets an authenticated conversation participant who holds chat permissions delete other participants' poll drafts by supplying the draft's numeric ID, because the poll controller never verified moderator or ownership rights before acting on that identifier. The flaw affects Talk versions prior to 20.1.8 and the 21.0.0-beta.1 through 21.1.2 range, and is rated CVSS 4.3 (network reachable, low privileges required, integrity-only impact) with an EPSS score of just 0.01% (2nd percentile), indicating a low-likelihood, low-priority issue. No public exploit code has been identified at the time of analysis, and CISA KEV does not list this CVE; vendor-released patches (20.1.8 and 21.1.2) are available.
Stored CSS injection in the Nextcloud Contacts app (versions prior to 5.5.4, 6.0.6, and 7.2.5) allows an authenticated user to place crafted markup in a contact's organisation or title field that is rendered unescaped when another user views that contact, enabling limited page defacement and CSS-based information leakage. Because the Nextcloud Server content security policy blocks JavaScript and other active content, the impact is confined to loading attacker-supplied stylesheets rather than arbitrary script execution, and exploitation requires the attacker to hold a valid account and the victim to open the affected contact entry. Publicly available exploit code exists, but the EPSS score is only 0.02% (5th percentile) and there is no evidence of confirmed active exploitation.
Nextcloud Tables allows you to create your own tables with individual columns. Prior to 0.8.7 and 0.9.4, authenticated users were able to view meta data of columns in other tables of the Tables app by modifying the numeric ID in a request. This vulnerability is fixed in 0.8.7 and 0.9.4.
An authenticated authorization bypass in the Nextcloud Tables app (CWE-639) lets a low-privilege user move a column from a table they created into a table owned by another user, corrupting the victim's table structure. All deployments of the Tables app below 0.8.6, and 0.9.0-beta.1 through versions before 0.9.3, are affected; the flaw requires an authenticated Nextcloud account (CVSS:3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N, base 4.3) and needs no victim interaction. Impact is limited to integrity of table definitions with no confidentiality or availability loss, EPSS is negligible at 0.02% (4th percentile) and no public exploit code was identified at time of analysis, so real-world priority is low. Vendor-released patch: 0.8.6 and 0.9.3.
Information disclosure in Nextcloud Desktop before 3.16.5 occurs when a user manually locks a file inside an end-to-end encrypted directory: the client sends the cleartext file path to the server, where an administrator can read it in logs. The exposure is limited to the path (no file contents or keys) and the CVSS vector (PR:H) confirms the attacker must already have high privileges, making this a low-severity issue (CVSS 2.7). No public exploit identified at time of analysis; EPSS is 0.03% (7th percentile).
Authenticated users with write access to a Nextcloud Deck board can spoof attachment file extensions by embedding Unicode right-to-left override (U+202E) characters in a filename, so a downloaded file is displayed with a trusted extension while its real type differs. The flaw affects Nextcloud Deck before 1.12.7, 1.14.4, and 1.15.1, and requires a second user to view the card and actively choose to download the misleadingly named attachment. Vendor patches (1.12.7, 1.14.4, 1.15.1) strip the RTLO character and render the basename and extension separately; the assessed impact is medium-severity UI spoofing with low real-world urgency, EPSS 0.01% (1st percentile), and no public exploit identified at time of analysis.
A security vulnerability in a group or team. (CVSS 3.5). Remediation should follow standard vulnerability management procedures. Vendor patch is available.
The Nextcloud Approval app allows approval or disapproval of files in the sidebar. Prior to 1.3.1 and 2.5.0, an authenticated user listed as a requester in a workflow can set another user’s file into the “pending approval” without access to the file by using the numeric file id. This vulnerability is fixed in 1.3.1 and 2.5.0.
Stored HTML injection in the Nextcloud Mail app's message list lets an authenticated user embed crafted markup into email subjects that is rendered for other mailbox users. The issue affects Nextcloud Mail prior to 5.5.3 (including 5.2.0-beta.1) and requires victim interaction, since a second user must open the Mail app and view the message list for the stored subject to render. Because the Nextcloud Server content security policy blocks JavaScript execution, impact is confined to HTML injection such as phishing, content spoofing, and UI manipulation rather than script-driven session compromise; EPSS is 0.02% (5th percentile) and no public exploit has been identified at time of analysis.
Information disclosure in Nextcloud Tables before 0.8.9, 0.9.6, and 1.0.1 lets any authenticated Nextcloud user read the sharing configuration of tables and views they do not own - which numeric table ID is shared with which users or groups and with what permissions - by calling the share-listing endpoints of the Tables API. Exploitation requires a valid Nextcloud session in an instance where the Tables app is enabled, and the exposure is limited to sharing metadata rather than the tables' contents, so there is no integrity or availability impact. The published CVSS of 5.3 (assessed as PR:L rather than the vendor's PR:N) combined with an EPSS score of only 0.02% (4th percentile) and no public exploit code identified makes this a low-to-moderate priority issue; vendor-released fixes exist in 0.8.9, 0.9.6, and 1.0.1.
A security vulnerability in Nextcloud Server and Enterprise Server (CVSS 4.3). Remediation should follow standard vulnerability management procedures. Vendor patch is available.
A security vulnerability in Nextcloud Calendar (CVSS 5.7). Risk factors: public PoC available. Vendor patch is available.
Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 31.0.1, non-privileged users can modify tags on files they should not have access to via bulk tagging. This vulnerability is fixed in 31.0.1.
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.19, 5.5.6, and 6.0.1, the calendar app allowed blindly booking appointments with a squential ID without known the appointment token. This vulnerability is fixed in 4.7.19, 5.5.6, and 6.0.1.
Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Server Enterprise prior to 31.0.12 and 32.0.3, a missing sanitization allowed malicious users to circumvent the content security policy when a malicious user manages to trick a user it viewing an uploaded SVG outside of the Nextcloud Servers web page.
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 6.0.3, the Calendar app generates participant tokens for meeting proposals using a hash function, allowing an attacker to compute valid participant tokens, which allowed them to request details and submit dates in meeting proposals. The tokens are not purely random generated. This vulnerability is fixed in 6.0.3.
A security vulnerability in Nextcloud Server (CVSS 4.5) that allows an authenticated user. Remediation should follow standard vulnerability management procedures. Vendor patch is available.
Cross-site scripting (XSS) vulnerability in a reachable files_pdfviewer example directory in Nextcloud with versions before 22.2.10.33, 23.0.12.29, 24.0.12.28, 25.0.13.23, 26.0.13.20, 27.1.11.20, 28.0.14.11, 29.0.16.8, 30.0.17, 31.0.10, and 32.0.1...
Collabora Online - Built-in CODE Server (richdocumentscode) provides a built-in server with all of the document editing features of Collabora Online. In versions prior to 25.04.702, Collabora Online has a Configuration-Dependent RCE (OS Command Injection) in richdocumentscode proxy. Users of Nextcloud with Collabora Online - Built-in CODE Server app can be vulnerable to attack via proxy.php and an intermediate reverse proxy. This vulnerability is fixed in 25.04.702.
Authenticated information disclosure in the Nextcloud Tables app (versions before 0.7.6, 0.8.8, and 0.9.5) lets a logged-in user trick the table-import flow into reading arbitrary files from the server. By invoking the import or preview import endpoint (ImportService.php) with a server-side path instead of an actual uploaded file, the attacker receives the parsed contents of any file whose format the bundled PhpSpreadsheet library can read, such as spreadsheets, CSV, ODS, or XML - resulting in high confidentiality impact with no integrity or availability effect (CVSS 3.1: 6.5, AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N). No public exploit code has been identified at time of analysis and the flaw is not listed as confirmed actively exploited (CISA KEV); EPSS is low at roughly 0.53% (43rd percentile), reflecting the authenticated precondition and the fact that the leak is confined to PhpSpreadsheet-parseable formats. This is a moderate-risk authenticated information disclosure flaw, not a top-tier priority.
Nextcloud Server is a self hosted personal cloud system. Rated low severity (CVSS 2.6), this vulnerability is remotely exploitable. No vendor patch available.
Nextcloud Server is a self hosted personal cloud system, and the Nextcloud Groupfolders app provides admin-configured folders shared by everyone in a group or team. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. This Allocation of Resources Without Limits vulnerability could allow attackers to exhaust system resources through uncontrolled allocation.
Nextcloud Desktop is the desktop sync client for Nextcloud. Rated medium severity (CVSS 5.0).
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 4.3), this vulnerability is no authentication required, low attack complexity. This Server-Side Request Forgery (SSRF) vulnerability could allow attackers to make the server perform requests to unintended internal or external resources.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 6.4), this vulnerability is remotely exploitable. No vendor patch available.
Nextcloud Server is a self hosted personal cloud system. Rated low severity (CVSS 3.5), this vulnerability is remotely exploitable, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
user_oidc app is an OpenID Connect user backend for Nextcloud. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Open Redirect vulnerability could allow attackers to redirect users to malicious websites via URL manipulation.
Nextcloud Tables allows users to to create tables with individual columns. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity.
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Rated medium severity (CVSS 5.7), this vulnerability is remotely exploitable, low attack complexity.
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
Nextcloud Tables allows users to to create tables with individual columns. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Uncontrolled Resource Consumption vulnerability could allow attackers to cause denial of service by exhausting system resources.
Nextcloud Server is a self hosted personal cloud system. Rated high severity (CVSS 8.2), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Nextcloud Server is a self hosted personal cloud system. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no authentication required. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.