What’s Vulnerable › Vulnerabilities

CVE-2021-42040

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-10-06 · updated 2026-06-17
• Weakness: CWE-835

Description

An issue was discovered in MediaWiki through 1.36.2. A parser function related to loop control allowed for an infinite loop (and php-fpm hang) within the Loops extension because egLoopsCountLimit is mishandled. This could lead to memory exhaustion.

Affected products

• Wikimedia Foundation MediaWiki: through 1.36.2

References

• https://gerrit.wikimedia.org/r/q/I0caf6f129f94612b5bcf406a171aa5ffedea1f80
• https://phabricator.wikimedia.org/T287347
• https://gerrit.wikimedia.org/r/q/I0caf6f129f94612b5bcf406a171aa5ffedea1f80
• https://phabricator.wikimedia.org/T287347

Get alerted when CVE-2021-42040 or the next vulnerability affects your stack