CVE-2025-61638 Sanitizer::validateAttributes data-XSS
An XSS vulnerability in MediaWiki and Parsoid allows attackers to inject malicious scripts via improper input neutralization in attribute validation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-61638?
CVE-2025-61638 is a cross-site scripting vulnerability in Mediawiki Mediawiki, published on 2 Feb 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-79
Which versions are affected by CVE-2025-61638?
It affects 2 products.
Products include Mediawiki Mediawiki, Wikimedia Parsoid.
How do I fix CVE-2025-61638?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-61638 being exploited?
There is no known exploitation of CVE-2025-61638 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Mediawiki Mediawiki
Sources
Also known as DEBIAN-CVE-2025-61638, GHSA-mq9h-r82m-hvhc, UBUNTU-CVE-2025-61638.