Symantec’s Windows kernel loading anti-virus is a nightmare
 

Symantec hit on a wizard wheeze for creating a more secure version of windows by jacking its security software into the kernel.


But according to Tavis Ormandy of Google's Project Zero team Symantec created a pile of pain for Windows users. But it turned out that the Symantec Antivirus Engine was vulnerable to a buffer overflow when parsing malformed portable-executable (PE) header files.

http://fudzilla.com/news/40717-syman...is-a-nightmare