Updated mediawiki packages fix security vulnerabilities:
MediaWiki before 1.22.3 does not block unsafe namespaces, such as a W3C XHTML namespace, in uploaded SVG files. Some client software may use these namespaces in a way that results in XSS. This was fixed by disallowing uploading SVG files using non-whitelisted namespaces (CVE-2014-2242).
MediaWiki before 1.22.3 performs token comparison that may be vulnerable to timing attacks. This was fixed by making token comparison use constant time (CVE-2014-2243).
MediaWiki before 1.22.3 could allow an attacker to perform XSS attacks, due to flaw with link handling in api.php. This was fixed such that it won't find links in the middle of api.php links (CVE-2014-2244).