simplemachines SMF versions 1.0.7 and prior plus 1.1rc2 and prior suffer from a IP spoofing vulnerability.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/46986/SMF1.0.7.txt
Source: https://packetstormsecurity.com/files/46986/SMF1.0.7.txt.html