CVE-2025-61638: Sanitizer::validateAttributes data-XSS

Severity: medium (CVSS 4.8 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, Wikimedia Foundation Parsoid. This vulnerability is associated with program files includes/parser/Sanitizer.Php, src/Core/Sanitizer.Php. This issue affects MediaWiki: from * before 1.39.14, 1.43.4, 1.44.1; Parsoid: from * before 0.16.6, 0.20.4, 0.21.1.

Affected products

Wikimedia Foundation MediaWiki: before 1.39.14; from 1.39.15 before 1.43.4; from 1.43.5 before 1.44.1 — fixed in 1.39.14, 1.43.4, 1.44.1
Wikimedia Parsoid: before 0.16.6; from 0.16.6 (excl.) before 0.20.4; from 0.20.4 (excl.) before 0.21.1 — fixed in 0.16.6, 0.20.4, 0.21.1

How to fix

Upgrade to a fixed version: Wikimedia Foundation MediaWiki 1.39.14, 1.43.4, 1.44.1; Wikimedia Parsoid 0.16.6, 0.20.4, 0.21.1. Check the vendor advisory for mitigations.

References

https://phabricator.wikimedia.org/T401099

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