Description
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation MediaWiki.

This vulnerability is associated with program files includes/Language/Language.Php, includes/Logging/BlockLogFormatter.Php, includes/Logging/LogFormatter.Php, includes/Logging/PatrolLogFormatter.Php, includes/Logging/RenameuserLogFormatter.Php, includes/Logging/TagLogFormatter.Php, includes/Specials/SpecialVersion.Php.



This issue affects MediaWiki: from * before 1.46.0, 1.45.4, 1.44.6, 1.43.9.
Published: 2026-07-01
Score: 0 Low
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

The vulnerability is a cross‑site scripting issue caused by improper neutralization of user‑controlled input in MediaWiki’s core log‑formatting code. Input that is incorporated into log entries can be rendered without escaping, allowing malicious code to be stored in the logs and executed when the log pages are viewed.

Affected Systems

MediaWiki installations from the earliest releases up to but not including version 1.46.0 are vulnerable, with documented affected releases being 1.45.4, 1.44.6, and 1.43.9. The problem resides in core files such as includes/Language.php, includes/Logging/BlockLogFormatter.php, LogFormatter.php, PatrolLogFormatter.php, RenameuserLogFormatter.php, TagLogFormatter.php, and includes/Specials/SpecialVersion.php.

Risk and Exploitability

The EPSS score of less than 1 % indicates a very low likelihood of exploitation, and the vulnerability is not included in the CISA KEV catalog. The likely attack vector involves a web page that displays logs; by inserting unescaped data into a log entry, an attacker can cause arbitrary JavaScript to run when the log page is viewed.

Generated by OpenCVE AI on August 4, 2026 at 08:02 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade MediaWiki to version 1.46.0 or later to apply the fixed log‑formatting logic.
  • Restrict access to log pages so that only trusted users can view them, limiting exposure while the vulnerability persists.
  • Review and sanitize any legacy log entries that may contain unescaped user input, or purge suspicious logs to prevent exploitation.

Generated by OpenCVE AI on August 4, 2026 at 08:02 UTC.

Tracking

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-6380-1 mediawiki security update
References
Link Providers
https://phabricator.wikimedia.org/T422995 cve-icon cve-icon
History

Thu, 02 Jul 2026 01:00:00 +0000

Type Values Removed Values Added
First Time appeared Wikimedia
Wikimedia mediawiki
Vendors & Products Wikimedia
Wikimedia mediawiki

Wed, 01 Jul 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 01 Jul 2026 15:30:00 +0000

Type Values Removed Values Added
Description Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation MediaWiki. This vulnerability is associated with program files includes/Language/Language.Php, includes/Logging/BlockLogFormatter.Php, includes/Logging/LogFormatter.Php, includes/Logging/PatrolLogFormatter.Php, includes/Logging/RenameuserLogFormatter.Php, includes/Logging/TagLogFormatter.Php, includes/Specials/SpecialVersion.Php. This issue affects MediaWiki: from * before 1.46.0, 1.45.4, 1.44.6, 1.43.9.
Title Core log entries for exceptions and XSS issues in log entry formatting code that may be caused by user-controlled input
Weaknesses CWE-79
References
Metrics cvssV4_0

{'score': 0, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N'}

Subscriptions

Mediawiki Mediawiki
Wikimedia Mediawiki
cve-icon MITRE

Status: PUBLISHED

Assigner: wikimedia-foundation

Published:

Updated: 2026-07-01T15:46:44.776Z

Reserved: 2026-06-27T13:32:41.613Z

Link: CVE-2026-58037

cve-icon Vulnrichment

Updated: 2026-07-01T15:46:39.619Z

cve-icon NVD

Status : Analyzed

Published: 2026-07-01T16:16:51.063

Modified: 2026-07-09T19:46:19.747

Link: CVE-2026-58037

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-04T08:15:06Z

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')