What’s Vulnerable › Vulnerabilities
CVE-2021-41800
- Severity: medium (CVSS 5.3 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.9% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2021-10-11 · updated 2026-06-17
- Weakness: CWE-770
Description
MediaWiki before 1.36.2 allows a denial of service (resource consumption because of lengthy query processing time). Visiting Special:Contributions can sometimes result in a long running SQL query because PoolCounter protection is mishandled.
Affected products
- Fedoraproject Fedora: 33, 34, 35
- Wikimedia Foundation MediaWiki: before 1.36.2 — fixed in 1.36.2
How to fix
Upgrade to a fixed version: Wikimedia Foundation MediaWiki 1.36.2. Check the vendor advisory for mitigations.
References
- https://github.com/wikimedia/mediawiki/commit/781caf83dba90c18349f930bbaaa0e89f003f874
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CJDYJQWT43GBD6GNQ4OW7JOZ6WQ6DZTN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MDBPECBWN6LWNSWIQMVXK6PP4YFEUYHA/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QNEAI2T3Y65I55ZB6UE6RMC662RZTGRX/
- https://lists.wikimedia.org/hyperkitty/list/wikitech-l%40lists.wikimedia.org/thread/2IFS5CM2YV4VMSODPX3J2LFHKSEWVFV5/
- https://phabricator.wikimedia.org/T284419
- https://security.gentoo.org/glsa/202305-24
- https://github.com/wikimedia/mediawiki/commit/781caf83dba90c18349f930bbaaa0e89f003f874
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CJDYJQWT43GBD6GNQ4OW7JOZ6WQ6DZTN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MDBPECBWN6LWNSWIQMVXK6PP4YFEUYHA/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QNEAI2T3Y65I55ZB6UE6RMC662RZTGRX/
- https://lists.wikimedia.org/hyperkitty/list/wikitech-l%40lists.wikimedia.org/thread/2IFS5CM2YV4VMSODPX3J2LFHKSEWVFV5/
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