MediaWiki XSS via Edit.Preview.Js (pre1.39.14/1.43.4/1.44.1)
CVE-2025-61637 Published on February 2, 2026
Stored XSS through system messages in MW Core
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.Action/mediawiki.Action.Edit.Preview.Js, resources/src/mediawiki.Page.Preview.Js.
This issue affects MediaWiki: from * before 1.39.14, 1.43.4, 1.44.1.
Weakness Type
What is a XSS Vulnerability?
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
CVE-2025-61637 has been classified to as a XSS vulnerability or weakness.
Products Associated with CVE-2025-61637
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Affected Versions
Wikimedia Foundation MediaWiki:- Version * and below 1.39.14, 1.43.4, 1.44.1 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.