Outpost Firewall PRO version 4.0 (and possibly older versions) hooks many functions in SSDT and in at least twelve cases it fails to validate arguments that come from user mode.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/52202/outpost-failures.txt
Source: https://packetstormsecurity.com/files/52202/outpost-failures.txt.html