Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-0669 is a high-severity Path Traversal (CWE-22) vulnerability in Mediawiki Mediawiki. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 32th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-0669 is an Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability, classified as CWE-22, in the CSS extension for Wikimedia Foundation's MediaWiki. The issue affects versions 1.44, 1.43, and 1.39 of the MediaWiki CSS extension and was published on 2026-01-07.
The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), meaning it is exploitable remotely over the network by unauthenticated attackers (PR:N) with low attack complexity and no user interaction. Attackers can traverse path restrictions to access files outside intended directories, resulting in high confidentiality impact through unauthorized data disclosure, while integrity and availability remain unaffected.
Advisories and patches are detailed in the Gerrit change at https://gerrit.wikimedia.org/r/q/Ia15bf3f2e5a341868568492a736ac3dbf706c22e and the Phabricator task at https://phabricator.wikimedia.org/T401526.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-1175
Vulnerability Data
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Wikimedia Foundation MediaWiki - CSS extension allows Path Traversal.This issue affects MediaWiki - CSS extension: 1.44, 1.43, 1.39.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.3.2
Mitigating Controls (NIST 800-53 r5) AI
Enforces the intended directory access authorizations that path traversal would otherwise bypass.
Input validation directly neutralizes special path elements before pathname construction occurs.
Least privilege reduces the impact of any unauthorized file access obtained via traversal.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.
PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development catches path traversal via static/dynamic analysis.
Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.
Application security requirements include rules for safe file handling and canonicalization.
Secure architecture principles require least-privilege file access and directory isolation.
Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.
Information access restriction limits which files an application may read or write.