Cyber Resilience

CVE-2026-0669

HighPublic PoC

Published: 07 January 2026

Published
07 January 2026
Modified
23 February 2026
KEV Added
—
Patch
—
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0011 28.7th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

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 28.7th 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 are NIST 800-53 AC-3 (Access Enforcement) and SI-10 (Information Input Validation).

Deeper analysis

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.

EU & UK References

Vulnerability details

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)
CWE-22

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
attack.mitre.org →
Why these techniques?

Path traversal in public-facing MediaWiki extension enables remote unauthenticated file read (T1190 initial access + T1005 local data disclosure).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2025-67484Same product: Mediawiki Mediawiki
CVE-2025-12824Shared CWE-22
CVE-2026-25965Shared CWE-22
CVE-2025-30567Shared CWE-22
CVE-2025-27098Shared CWE-22
CVE-2024-55457Shared CWE-22
CVE-2026-35485Shared CWE-22
CVE-2024-54909Shared CWE-22
CVE-2026-3405Shared CWE-22
CVE-2025-41368Shared CWE-22

Affected Assets

css project
css
all versions

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SI-2 Flaw Remediation good match
prevent

Directly remediates the path traversal flaw in MediaWiki CSS extension versions 1.44, 1.43, and 1.39 by identifying, reporting, and applying available patches.

SI-10 Information Input Validation good match
prevent

Requires validation of pathnames and file inputs to ensure they remain within restricted directories, preventing traversal attacks.

AC-3 Access Enforcement good match
prevent

Enforces logical access controls on system resources, blocking unauthorized file reads resulting from path traversal exploitation.

References