ClamAV

ClamAV: A reliable antivirus solution capable of detecting a large number of viruses, worms and trojans to secure your computer against digital threats

ClamAV is a powerful antivirus software solution that can detect a wide array of threats inside files and email messages, using several detection methods for viruses, trojans, worms, and malware.

The tool can be most useful to network administrators as it was designed for email servers. It bundles a number of command line tools that can be used to perform on-demand and multi-threaded virus scans, as well as update the virus database.

ClamAV can be controlled exclusively via command line and configured by customizing the sample configuration files. While this is not particularly user-friendly and aimed more at professional individuals, the program uses an insignificant amount of system resources, despite the fact it can reliable detect infections, even when it needs to process a large number of emails.

On the official website, you can access various online resources that can help you learn how to use ClamAV.