CVE-2026-34091

User localization leaked by AbuseFilter + EventStream

Published May 11, 2026 CVSS 4.0 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation MediaWiki.

This issue affects MediaWiki: from * before 1.43.7, 1.44.4, 1.45.2.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DSA Debian DSA DSA-6208-1 mediawiki security update
References
History
Type Values Removed Values Added
First Time appeared Mediawiki
Mediawiki mediawiki
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:*
Vendors & Products Mediawiki
Mediawiki mediawiki
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}

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

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation MediaWiki. This issue affects MediaWiki: from * before 1.43.7, 1.44.4, 1.45.2.
Title User localization leaked by AbuseFilter + EventStream
Weaknesses CWE-200
References
Metrics cvssV4_0

{'score': 5.5, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/R:U'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
wikimedia-foundation
Published
Updated
May 11, 2026, 4:03 PM
Reserved
Mar 25, 2026, 5:15 PM
Status
Analyzed
Published
May 11, 2026, 4:17 PM
Modified
Oct 26, 2026, 6:10 PM