Nextcloud
CVE-2023-39954
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V14 - Data Protection Encryption of sensitive data
|
| Impact | CVSS score of 8.1 (HIGH). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAI
user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, low attack complexity.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-311. user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, an attacker that obtained at least read access to a snapshot of the database can impersonate the Nextcloud server towards linked servers. user_oidc 1.3.3 contains a patch. No known workarounds are available. Affected products include: Nextcloud User Oidc. Version information: version 1.0.0.
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, an attacker that obtained at least read access to a snapshot of the database can impersonate the Nextcloud server towards linked servers. user_oidc 1.3.3 contains a patch. No known workarounds are available.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)NVD
Nextcloud server is an open source home cloud implementation. Rated high severity (CVSS 8.8), this vulnerability is remo
A too lax check in Nextcloud Talk 6.0.4, 7.0.2 and 8.0.7 allowed a code injection when a not correctly sanitized talk co
Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Rated critical severity (CVSS 9.8),
Unauthenticated OS command injection in the Collabora Online Built-in CODE Server Nextcloud app (richdocumentscode) befo
Unauthenticated vector-store tampering in Nextcloud MCP Server before 0.117.2 lets any network attacker who can reach th
Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.1.2, 9.0.6, and 8.2.9 suffer from SMB User Authenti
NextCloud Cookbook is a recipe library app. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable,
Nextcloud server is an open source home cloud implementation. Rated high severity (CVSS 8.8), this vulnerability is remo
Nextcloud Desktop Client prior to 3.1.3 is vulnerable to resource injection by way of missing validation of URLs, allowi
lib/Controller/ExtractionController.php in the Extract add-on before 1.2.0 for Nextcloud allows Remote Code Execution vi
Authorization bypass in Windmill 1.56.0-1.614.0 enables Operator role users to escalate privileges to remote code execut
Insufficient protection of the server-side encryption keys in Nextcloud Server 19.0.1 allowed an attacker to replace the
NVD
CVE.org
EPSS
GitHub
Exploit-DB