ClamAV

Clam AntiVirus is an open source (GPL) anti-virus toolkit for UNIX. It provides a number of utilities including a flexible and scalable multi-threaded daemon, a command line scanner and advanced tool for automatic database updates. Because ClamAV’s main use is on file/mail servers for Windows desktops, it primarily detects Windows viruses and malware with its built-in signatures.

Usage

Updating database

Update the virus definitions with:

freshclam

The database files are saved in:

/var/lib/clamav/daily.cvd
/var/lib/clamav/main.cvd
/var/lib/clamav/bytecode.cvd

Start/Enableclamav-freshclam.service so that the virus definitions are kept recent.

Starting the daemon

Note:

• You will need to run freshclam before starting the service for the first time or you will run into trouble/errors which will prevent ClamAV from starting correctly.
• The daemon is not needed if you only want to perform stand-alone scans.

The service is called clamav-daemon.service.

Scanning for viruses

clamscan can be used to scan certain files, home directories, or an entire system:

clamscan myfile
clamscan --recursive --infected /home/archie
clamscan --recursive --infected --exclude-dir='^/sys|^/dev' /

If you would like clamscan to remove the infected file add to the command the --remove option, or you can use --move=/dir to quarantine them.

You may also want clamscan to scan larger files. In this case, append the options --max-filesize=4000M and --max-scansize=4000M to the command. ‘4000M’ is the largest possible value, and may be lowered as necessary.

Using the -l /path/to/file option will print the clamscan logs to a text file for locating reported infections.