Secunia Security Advisory – s.masugata has reported a vulnerability in PHP, which potentially can be exploited by malicious people to use it as an open mail relay.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/41822/sa17763.txt
Source: https://packetstormsecurity.com/files/41822/Secunia-Security-Advisory-17763.html