CVE-2026-39934 Growth Experiments ReassignMenteesJob runs as an infinite loop
An attacker can trigger an infinite loop in the ReassignMenteesJob via a race condition, causing denial of service in MediaWiki GrowthExperiments.
- 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-2026-39934?
CVE-2026-39934 is a medium-severity vulnerability in Mediawiki - GrowthExperiments 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
Loop with unreachable exit condition ('infinite loop') vulnerability in The Wikimedia Foundation Mediawiki - GrowthExperiments Extension allows Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions. This issue was remediated only on the `master` branch.
Weakness: CWE-835
Which versions are affected by CVE-2026-39934?
How do I fix CVE-2026-39934?
No fix has been published for CVE-2026-39934 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-39934 being exploited?
There is no known exploitation of CVE-2026-39934 in the wild and no public exploit code.
Sources
Also known as GHSA-cgh3-rgf8-476j.