Researcher Claims Online Anti-virus Scanners Buggy:
"Online scanners from Symantec, McAfee and Panda all contain buffer overflows. One researcher claims an attacker could execute arbitrary code, another just that they could crash the browser. Panda reports their software has been fixed and Symantec denies there is a problem at all. "

http://www.eweek.com/article2/0,1759,1563092,00.asp