PHP version 5.2.6 suffers from a SAPI php_getuid() overload vulnerability.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/72724/php526-getuid.txt
Source: https://packetstormsecurity.com/files/72724/PHP-5.2.6-SAPI-php_getuid-Overload.html