usercp_register.php in phpBB 2.0.17 allows remote attackers to modify regular expressions and execute PHP code via the signature_bbcode_uid parameter, as demonstrated by injecting an “e” modifier into a preg_replace statement.
marc.info/?l=bugtraq&m=113081113317600&w=2
secunia.com/advisories/17366
secunia.com/advisories/18098
securityreason.com/securityalert/130
securitytracker.com/id?1015121
www.debian.org/security/2005/dsa-925
www.hardened-php.net/advisory_172005.75.html
www.osvdb.org/20391
www.securityfocus.com/bid/15243
www.vupen.com/english/advisories/2005/2250