CVE-2026-39933 Multiple XSS vulnerabilities in GlobalWatchlist
Cross-site scripting vulnerabilities in the MediaWiki GlobalWatchlist extension allow attackers to inject malicious scripts, potentially compromising user sessions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-39933?
CVE-2026-39933 is a medium-severity cross-site scripting vulnerability in The Wikimedia Foundation Mediawiki - GlobalWatchlist Extension, published on 7 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in The Wikimedia Foundation Mediawiki - GlobalWatchlist Extension allows Cross-Site Scripting (XSS). The issue has been remediated on the `master` branch, and in the release branches for MediaWiki versions 1.43, 1.44, and 1.45.
Weakness: CWE-79
Which versions are affected by CVE-2026-39933?
How do I fix CVE-2026-39933?
No fix has been published for CVE-2026-39933 yet. Limit exposure of the affected software until one is available.
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-2026-39933 being exploited?
There is no known exploitation of CVE-2026-39933 in the wild and no public exploit code.
Sources
Also known as GHSA-333p-mjpr-3q3c.