Nextcloud

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.

Display name spoofing bypass in OpenClaw Nextcloud Talk plugin before 2026.2.6.

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]

Nextcloud Twofactor WebAuthn is the WebAuthn Two-Factor Provider for Nextcloud. Prior to 1.4.2 and 2.4.1, a missing ownership check allowed an attack to take-away a 2FA webauthn device when correctly guessing a 80-128 character long random string of letters, numbers and symbols. The victim would then be prompted to register a new device on the next login. The attacker can not authenticate as the victim. This vulnerability is fixed in 1.4.2 and 2.4.1.

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.14.6 and 1.15.2, a bug in the permission logic allowed users with "Can share" permission to modify the permissions of other recipients. This vulnerability is fixed in 1.14.6 and 1.15.2.

Nextcloud talk is a video & audio conferencing app for Nextcloud. Prior to 20.1.8 and 21.1.2, a participant with chat permissions was able to delete poll drafts of other participants within the conversation based on their numeric ID. This vulnerability is fixed in 20.1.8 and 21.1.2.

Contacts app for Nextcloud easily syncs contacts from various devices with your Nextcloud and allows editing. Prior to 5.5.4, 6.0.6, and 7.2.5, a malicious user was able to modify their organisation and title field to load additional CSS files. Javascript and other options were correctly blocked by the content security policy of the Nextcloud Server code. This vulnerability is fixed in 5.5.4, 6.0.6, and 7.2.5.

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.

Nextcloud Tables allows you to create your own tables with individual columns. Prior to 0.8.6 and 0.9.3, a malicious user was able to create their own table and then move a column to a victims table. This vulnerability is fixed in 0.8.6 and 0.9.3.

Nextcloud Desktop is the desktop sync client for Nextcloud. Prior to 3.16.5, when trying to manually lock a file inside an end-to-end encrypted directory, the path of the file was sent to the server unencrypted, making it possible for administrators to see it in log files. This vulnerability is fixed in 3.16.5.

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.12.7, 1.14.4, and 1.15.1, file extension can be spoofed by using RTLO characters, tricking users into download files with a different extension than what is displayed. This vulnerability is fixed in 1.12.7, 1.14.4, and 1.15.1.

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.

Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Prior to 5.5.3, a stored HTML injection in the Mail app's message list allowed an authenticated user to inject HTML into the email subjects. Javascript was correctly blocked by the content security policy of the Nextcloud Server code.

Nextcloud Tables allows you to create your own tables with individual columns. Prior to 0.8.9, 0.9.6, and 1.0.1, the information which table (numeric ID) is shared with which groups or users and the respective permissions was not limited to privileged users. This vulnerability is fixed 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.

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.