The XML-RPC implementation (xmlrpc.php) in WordPress before 2.3.3, when registration is enabled, allows remote attackers to edit posts of other blog users via unknown vectors.
https://www.redhat.com/archives/fedora-package-announce/2008-February/msg00416.html
https://www.redhat.com/archives/fedora-package-announce/2008-February/msg00349.html
https://bugzilla.redhat.com/show_bug.cgi?id=431547
http://www.vupen.com/english/advisories/2008/0448
http://www.village-idiot.org/archives/2008/02/02/wordpress-232-exploit-confirmed/
http://www.securitytracker.com/id?1019316
http://www.securityfocus.com/bid/27669
http://www.debian.org/security/2008/dsa-1601
http://wordpress.org/development/2008/02/wordpress-233/
http://secunia.com/advisories/30960