An issue was discovered in the AbuseFilter extension in MediaWiki through 1.36. If the MediaWiki:Abusefilter-blocker message is invalid within the content language, the filter user falls back to the English version, but that English version could also be invalid on a wiki. This would result in a fatal error, and potentially fail to block or restrict a potentially nefarious user.

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).

In MediaWiki before 1.31.15, 1.32.x through 1.35.x before 1.35.3, and 1.36.x before 1.36.1, bots have certain unintended API access. When a bot account has a "sitewide block" applied, it is able to still "purge" pages through the MediaWiki Action API (which a "sitewide block" should have prevented).

GlobalNewFiles is a mediawiki extension. Versions prior to 48be7adb70568e20e961ea1cb70904454a671b1d are affected by an uncontrolled resource consumption vulnerability. A large amount of page moves within a short space of time could overwhelm Database servers due to improper handling of load balancing and a lack of an appropriate index. As a workaround, one may avoid use of the extension unless additional rate limit at the MediaWiki level or via PoolCounter / MySQL is enabled. A patch is available in version 48be7adb70568e20e961ea1cb70904454a671b1d.

ManageWiki is an extension to the MediaWiki project. The 'wikiconfig' API leaked the value of private configuration variables set through the ManageWiki variable to all users. This has been patched by https://github.com/miraheze/ManageWiki/compare/99f3b2c8af18...befb83c66f5b.patch. If you are unable to patch set `$wgAPIListModules['wikiconfig'] = 'ApiQueryDisabled';` or remove private config as a workaround.

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 improperly handled account blocks for certain automatically created MediaWiki user accounts, thus allowing nefarious users to remain unblocked.

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. 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 PageForms extension for MediaWiki through 1.35.2. Crafted payloads for Token-related query parameters allowed for XSS on certain PageForms-managed MediaWiki pages.

An issue was discovered in the CommentBox extension for MediaWiki through 1.35.2. Via crafted configuration variables, a malicious actor could introduce XSS payloads into various layers.

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.

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 AbuseFilter extension for MediaWiki through 1.35.2. It incorrectly logged sensitive suppression deletions, which should not have been visible to users with access to view AbuseFilter log data.

An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. The page_recent_contributors leaked the existence of certain deleted MediaWiki usernames, related to rev_deleted.

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. Users can bypass intended restrictions on deleting pages in certain "fast double move" situations. MovePage::isValidMoveTarget() uses FOR UPDATE, but it's only called if Title::getArticleID() returns non-zero with no special flags. Next, MovePage::moveToInternal() will delete the page if getArticleID(READ_LATEST) is non-zero. Therefore, if the page is missing in the replica DB, isValidMove() will return true, and then moveToInternal() will unconditionally delete the page if it can be found in the master.

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. Special:Contributions can leak that a "hidden" user exists.

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. ContentModelChange does not check if a user has correct permissions to create and set the content model of a nonexistent page.

An issue was discovered in MediaWiki before 1.31.13 and 1.32.x through 1.35.x before 1.35.2. When using the MediaWiki API to "protect" a page, a user is currently able to protect to a higher level than they currently have permissions for.