Mediawiki : Security Vulnerabilities, CVEs, Published In January 2014

MediaWiki 1.22.x before 1.22.2, 1.21.x before 1.21.5, and 1.19.x before 1.19.11, when DjVu or PDF file upload support is enabled, allows remote attackers to execute arbitrary commands via shell metacharacters in (1) the page parameter to includes/media/DjVu.php; (2) the w parameter (aka width field) to thumb.php, which is not properly handled by includes/media/PdfHandler_body.php; and possibly unspecified vectors in (3) includes/media/Bitmap.php and (4) includes/media/ImageHandler.php.

The CentralAuth extension for MediaWiki 1.19.x before 1.19.8, 1.20.x before 1.20.7, and 1.21.x before 1.21.2 caches a valid CentralAuthUser object in the centralauth_User cookie even when a user has not successfully logged in, which allows remote attackers to bypass authentication without a password.