sapi/cgi/cgi_main.c in PHP before 5.3.13 and 5.4.x before 5.4.3 when configured as a CGI script (aka php-cgi) does not properly handle query strings that contain a %3D sequence but no = (equals sign) character which allows remote attackers to execute arbitrary code by placing command-line options in the query string related to lack of skipping a certain php_getopt for the 'd' case. NOTE: this vulnerability exists because of an incomplete fix for CVE-2012-1823.