Launchpad.net

CVE 2009-0737

Multiple cross-site scripting (XSS) vulnerabilities in the web-based installer (config/index.php) in MediaWiki 1.6 before 1.6.12, 1.12 before 1.12.4, and 1.13 before 1.13.4, when the installer is in active use, allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.

See the CVE page on Mitre.org for more details.