api.php in MediaWiki before 1.15.5 does not prevent use of public caching headers for private data, which allows remote attackers to bypass intended access restrictions and obtain sensitive information by retrieving documents from an HTTP proxy cache that has been used by a victim.
lists.fedoraproject.org/pipermail/package-announce/2011-April/058588.html
lists.fedoraproject.org/pipermail/package-announce/2011-April/058910.html
lists.fedoraproject.org/pipermail/package-announce/2011-April/059232.html
lists.fedoraproject.org/pipermail/package-announce/2011-April/059235.html
lists.wikimedia.org/pipermail/mediawiki-announce/2010-July/000092.html
openwall.com/lists/oss-security/2010/07/29/4
svn.wikimedia.org/viewvc/mediawiki?view=revision&revision=69776
www.securityfocus.com/bid/42019
bugzilla.redhat.com/show_bug.cgi?id=620224
bugzilla.redhat.com/show_bug.cgi?id=620226
bugzilla.wikimedia.org/show_bug.cgi?id=24565