CVE-2025-11261: Stored i18n XSS exposed by security patch for T402077

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-03 · updated 2026-06-17
Weakness: CWE-79

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 resources/src/mediawiki.Language/mediawiki.Language.Js. This issue affects MediaWiki: from * before 1.39.15, 1.43.5, 1.44.2.

Affected products

Wikimedia Foundation MediaWiki: before 1.39.15; from 1.43.0 before 1.43.5; from 1.44.0 before 1.44.2 — fixed in 1.39.15, 1.43.5, 1.44.2

How to fix

Upgrade to a fixed version: Wikimedia Foundation MediaWiki 1.39.15, 1.43.5, 1.44.2. Check the vendor advisory for mitigations.

References

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