An issue was discovered in the AbuseFilter extension through 1.34 for MediaWiki. Previously hidden (restricted) AbuseFilter filters were viewable (or their differences were viewable) to unprivileged users, thus disclosing potentially sensitive information.

An issue was discovered in the CheckUser extension through 1.34 for MediaWiki. Certain sensitive information within oversighted edit summaries made available via the MediaWiki API was potentially visible to users with various levels of access to this extension. Said users should not have been able to view these oversighted edit summaries via the MediaWiki API.

mediawiki allows deleted text to be exposed

In MediaWiki through 1.33.0, Special:Redirect allows information disclosure of suppressed usernames via a User ID Lookup.

In the OAuth2 Client extension before 0.4 for MediaWiki, a CSRF vulnerability exists due to the OAuth2 state parameter not being checked in the callback function.

In the MobileFrontend extension 1.31 through 1.33 for MediaWiki, XSS exists within the edit summary field in includes/specials/MobileSpecialPageFeed.php.

Wikimedia MediaWiki through 1.32.1 has Incorrect Access Control. Suppressed log in RevisionDelete page is exposed. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

MediaWiki through 1.32.1 has Incorrect Access Control. Suppressed username or log in Special:EditTags are exposed. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

Wikimedia MediaWiki 1.23.0 through 1.32.1 has an information leak. Privileged API responses that include whether a recent change has been patrolled may be cached publicly. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

Wikimedia MediaWiki 1.27.0 through 1.32.1 might allow DoS. Passing invalid titles to the API could cause a DoS by querying the entire watchlist table. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

An Incorrect Access Control vulnerability was found in Wikimedia MediaWiki 1.18.0 through 1.32.1. It is possible to bypass the limits on IP range blocks ($wgBlockCIDRLimit) by using the API. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

Wikimedia MediaWiki 1.30.0 through 1.32.1 has XSS. Loading user JavaScript from a non-existent account allows anyone to create the account, and perform XSS on users loading that script. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

Wikimedia MediaWiki through 1.32.1 allows CSRF.

An Incorrect Access Control vulnerability was found in Wikimedia MediaWiki 1.27.0 through 1.32.1. Directly POSTing to Special:ChangeEmail would allow for bypassing re-authentication, allowing for potential account takeover.

MediaWiki through 1.32.1 has Incorrect Access Control (issue 1 of 3). A spammer can use Special:ChangeEmail to send out spam with no rate limiting or ability to block them. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

Mediawiki 1.31 before 1.31.1 misses .htaccess files in the provided tarball used to protect some directories that shouldn't be web accessible.

Mediawiki 1.31 before 1.31.1, 1.30.1, 1.29.3 and 1.27.5 contains a flaw where BotPasswords can bypass CentralAuth's account lock

Mediawiki 1.31 before 1.31.1, 1.30.1, 1.29.3 and 1.27.5 contains an information disclosure flaw in the Special:Redirect/logid

Mediawiki 1.31 before 1.31.1, 1.30.1, 1.29.3 and 1.27.5 contains a flaw where contrary to the documentation, $wgRateLimits entry for 'user' overrides that for 'newbie'.

MediaWiki 1.18.0 allows remote attackers to obtain the installation path via vectors related to thumbnail creation.