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.
https://security.gentoo.org/glsa/202305-24
https://phabricator.wikimedia.org/T284419
https://github.com/wikimedia/mediawiki/commit/781caf83dba90c18349f930bbaaa0e89f003f874