Multiple PHP remote file inclusion vulnerabilities in the Keep It Simple Guest Book (KISGB) allow remote attackers to execute arbitrary PHP code via a URL in the (1) path_to_themes parameter in (a) authenticate.php, and the (2) default_path_for_themes parameter in (b) admin.php and (c) upconfig.php.
PHP remote file inclusion vulnerability in authenticate.php in Keep It Simple Guest Book (KISGB), when executing PHP through CGI, allows remote attackers to execute arbitrary PHP code via a URL in the default_path_to_themes parameter.