MediaWiki 1.8.1, and other versions before 1.13.3, when the wgShowExceptionDetails variable is enabled, sometimes provides the full installation path in a debugging message, which might allow remote attackers to obtain sensitive information via unspecified requests that trigger an uncaught exception.
lists.wikimedia.org/pipermail/mediawiki-announce/2008-December/000080.html
secunia.com/advisories/33349
www.mediawiki.org/wiki/Manual:%24wgShowExceptionDetails
www.redhat.com/archives/fedora-package-announce/2008-December/msg01256.html
www.redhat.com/archives/fedora-package-announce/2008-December/msg01309.html