MediaWiki 1.27.x before 1.27.1 might allow remote attackers to bypass intended session access restrictions by leveraging a call to the UserGetRights function after Session::getAllowedUserRights.

MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1, when $wgBlockDisablesLogin is true, might allow remote attackers to obtain sensitive information by leveraging failure to terminate sessions when a user account is blocked.

MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1 allows remote authenticated users with undelete permissions to bypass intended suppressrevision and deleterevision restrictions and remove the revision deletion status of arbitrary file revisions by using Special:Undelete.

MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1 do not properly normalize IP addresses containing zero-padded octets, which might allow remote attackers to bypass intended access restrictions by using an IP address that was not supposed to have been allowed.

The (1) Special:MyPage, (2) Special:MyTalk, (3) Special:MyContributions, (4) Special:MyUploads, and (5) Special:AllMyUploads pages in MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1 allow remote attackers to obtain sensitive user login information via crafted links combined with page view statistics.

The User::matchEditToken function in includes/User.php in MediaWiki before 1.23.12 and 1.24.x before 1.24.5 does not perform token comparison in constant time before returning, which allows remote attackers to guess the edit token and bypass CSRF protection via a timing attack, a different vulnerability than CVE-2015-8624.

MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1 do not properly sanitize parameters when calling the cURL library, which allows remote attackers to read arbitrary files via an @ (at sign) character in unspecified POST array parameters.

The User::matchEditToken function in includes/User.php in MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1 does not perform token comparison in constant time before determining if a debugging message should be logged, which allows remote attackers to guess the edit token and bypass CSRF protection via a timing attack, a different vulnerability than CVE-2015-8623.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1, when is configured with a relative URL, allows remote authenticated users to inject arbitrary web script or HTML via wikitext, as demonstrated by a wikilink to a page named "javascript:alert('XSS!')."

The User::randomPassword function in MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1 generates passwords smaller than $wgMinimalPasswordLength, which makes it easier for remote attackers to obtain access via a brute-force attack.