An issue was discovered in the CentralAuth extension in MediaWiki through 1.36. The Special:GlobalRenameRequest page is vulnerable to infinite loops and denial of service attacks when a user's current username is beyond an arbitrary maximum configuration value (MaxNameChars).

An issue was discovered in the CentralAuth extension in MediaWiki through 1.36. Autoblocks for CentralAuth-issued suppression blocks are not properly implemented.

An issue was discovered in the Translate extension in MediaWiki through 1.36. The Aggregategroups Action API module does not validate the parameter for aggregategroup when action=remove is set, thus allowing users with the translate-manage right to silently delete various groups' metadata.

An XSS issue was discovered in the SportsTeams extension in MediaWiki through 1.36. Within several special pages, a privileged user could inject arbitrary HTML and JavaScript within various data fields. The attack could easily propagate across many pages for many users.

An issue was discovered in the Oauth extension for MediaWiki through 1.35.2. It did not validate the oarc_version (aka oauth_registered_consumer.oarc_version) parameter's length.

An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. It incorrectly executed certain rules related to blocking accounts after account creation. Such rules would allow for user accounts to be created while blocking only the IP address used to create an account (and not the user account itself). Such rules could also be used by a nefarious, unprivileged user to catalog and enumerate any number of IP addresses related to these account creations.

An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. A MediaWiki user who is partially blocked or was unsuccessfully blocked could bypass AbuseFilter and have their edits completed.

An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. Its AbuseFilterCheckMatch API reveals suppressed edits and usernames to unprivileged users through the iteration of crafted AbuseFilter rules.

An issue was discovered in the CheckUser extension for MediaWiki through 1.35.2. MediaWiki usernames with trailing whitespace could be stored in the cu_log database table such that denial of service occurred for certain CheckUser extension pages and functionality. For example, the attacker could turn off Special:CheckUserLog and thus interfere with usage tracking.

An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. The Special:AbuseFilter/examine form allowed for the disclosure of suppressed MediaWiki usernames to unprivileged users.