In an advisory from TEXONET, it has been reported that TrendMicro's PC-cillin antivirus has a buffer overflow in it's email scanning utility. Instead of connecting directly to the outside world, the user's e-mail program connects to a proxy -- a program that's running on the user's own machine. The proxy invokes the antivirus on outgoing mail, and only allows a message to pass if it's free of malware.

Unfortunately, according to an advisory from Texonet, a Swedish security company, the proxy contains a buffer overflow vulnerability. If a program on the user's machine sends the proxy a large stream of "junk" characters that does not contain an end-of-line character, the buffer overflows and code can be executed.

TRENDMICRO, the maker of PC-cillin, has acknowledged this issue and is offering a solution.