PunBB 1.2.9, used alone or with F-ART BLOG:CMS, may trust a client's IP address as specified in the X-Forwarded-For HTTP header rather than the TCP/IP stack, which allows remote attackers to misrepresent their IP address by sending a modified header.
admin_loader.php in PunBB 1.2.1 allows remote attackers to read arbitrary files via the plugin parameter.
PunBB 1.2.9, when used alone or with F-ART BLOG:CMS, includes config.php before calling the unregister_globals function, which allows attackers to obtain unspecified sensitive information.