The MITRE CVE dictionary describes this issue as:
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 lack an = (equals sign) character, which allows remote attackers to cause a denial of service (resource consumption) by placing command-line options in the query string, related to lack of skipping a certain php_getopt for the 'T' case. NOTE: this vulnerability exists because of an incomplete fix for CVE-2012-1823.
Find out more about CVE-2012-2336 from the
MITRE CVE dictionary dictionary and