Check this out – Clam AntiVirus (http://clamav.net) is an open source antivirus package, and runs on UNIX. It easily hooks into sendmail, and can scan all incoming mail, including contents of zip files as well as following html links back to their source to see if there is malicious intent on the web site. I like looking in my “viruses” mailbox to see what it filtered out that day. But wait, there’s more… What about Windows?
In addition to scanning email on UNIX, there are command line programs you can use to scan files or directories, which means you get antivirus capability to whatever programs you develop. NICE.
But it doesn’t end there – there’s a Windows port as well – http://www.clamwin.com. This can be installed and scan files and directories on your PC. Like the UNIX version, it checks the internet for virus signature updates and can be configured to download them automatically. Automatically up to date!
The one down side about clamwin is that it does not scan programs as they are run, catching viruses in the act. But wait, it’s open source, right? YES! So there are other programs out there that leverage ClamWin to do exactly what is needed. Winpooch (http://winpooch.free.fr/home/index.php) by itself will stop suspicious programs from doing things they shouldn’t, but also has hooks into ClamWin if installed, and will scan files for viruses before they are run. SWEET! There is also a Firefox extension that hooks into ClamWin and scans files as they are downloaded to make sure there are no viruses in them. (The current extension does not work with the latest version of Firefox, but good things are still to come, to be sure).
Open source rocks!