CVE-2025-61634 HTML rest endpoint needs PoolCounter and proper parser cache check
An attacker can exploit a path traversal flaw in the HTML REST endpoint to read or modify files, requiring an upgrade to secure MediaWiki installations.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-61634?
CVE-2025-61634 is a path traversal vulnerability in Mediawiki Mediawiki, published on 2 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Vulnerability in Wikimedia Foundation MediaWiki. This vulnerability is associated with program files includes/Rest/Handler/PageHTMLHandler.Php.
This issue affects MediaWiki: from * before 1.39.14, 1.43.4, 1.44.1.
Weakness: CWE-22
Which versions are affected by CVE-2025-61634?
It affects 1 product.
Products include Mediawiki Mediawiki.
How do I fix CVE-2025-61634?
Upgrade to a fixed version.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2025-61634 being exploited?
There is no known exploitation of CVE-2025-61634 in the wild and no public exploit code.
Other vulnerabilities in Mediawiki Mediawiki
Sources
Also known as DEBIAN-CVE-2025-61634, GHSA-xh35-43pp-33v2, UBUNTU-CVE-2025-61634.