Cross-site request forgery (CSRF) vulnerability in Special:Upload in MediaWiki 1.17.x before 1.17.3 and 1.18.x before 1.18.2 allows remote attackers to hijack the authentication of unspecified victims for requests that upload files.

The wikitext parser in MediaWiki 1.17.x before 1.17.3 and 1.18.x before 1.18.2 allows remote attackers to cause a denial of service (infinite loop) via certain input, as demonstrated by the padleft function.

Multiple cross-site request forgery (CSRF) vulnerabilities in MediaWiki 1.17.x before 1.17.3 and 1.18.x before 1.18.2 allow remote attackers to hijack the authentication of users with the block permission for requests that (1) block a user via a request to the Block module or (2) unblock a user via a request to the Unblock module.

MediaWiki 1.17.x before 1.17.3 and 1.18.x before 1.18.2 uses weak random numbers for password reset tokens, which makes it easier for remote attackers to change the passwords of arbitrary users.

Cross-site scripting (XSS) vulnerability in the wikitext parser in MediaWiki 1.17.x before 1.17.3 and 1.18.x before 1.18.2 allows remote attackers to inject arbitrary web script or HTML via a crafted page with "forged strip item markers," as demonstrated using the CharInsert extension.

Cross-site scripting (XSS) vulnerability in the outputPage function in includes/SkinTemplate.php in MediaWiki before 1.17.5, 1.18.x before 1.18.4, and 1.19.x before 1.19.1 allows remote attackers to inject arbitrary web script or HTML via the uselang parameter to index.php/Main_page.

MediaWiki before 1.17.1 allows remote attackers to obtain the page titles of all restricted pages via a series of requests involving the (1) curid or (2) oldid parameter.

MediaWiki before 1.17.1 does not check for read permission before handling action=ajax requests, which allows remote attackers to obtain sensitive information by (1) leveraging the SpecialUpload::ajaxGetExistsWarning function, or by (2) leveraging an extension, as demonstrated by the CategoryTree, ExtTab, and InlineEditor extensions.

includes/User.php in MediaWiki before 1.16.5, when wgBlockDisablesLogin is enabled, does not clear certain cached data after verification of an auth token fails, which allows remote attackers to bypass authentication by creating crafted wikiUserID and wikiUserName cookies, or by leveraging an unattended workstation.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.16.5, when Internet Explorer 6 or earlier is used, allows remote attackers to inject arbitrary web script or HTML via an uploaded file accessed with a dangerous extension such as .shtml at the end of the query string, in conjunction with a modified URI path that has a %2E sequence in place of the . (dot) character. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-1578 and CVE-2011-1587.