ClamAV

Installation

   yum install clamav
   freshclam
   service clamd start
   chkconfig clamd on

You’ll have to update only once; a cron job kicks in later.

Testing

Send youself a plaintext message with this
body:

   X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*

The mail log should report this (but still deliver the message)

   amavis[14234]: (14234-03) Blocked INFECTED (Eicar-Test-Signature) 
   {DiscardedInbound,Quarantined}, [209.85.216.181]:48846 [209.85.216.181] 
   ping@example.com -> pong@example.com, quarantine: virus-1wR6qb-51v7G, 
   Message-ID: CAM=+e3EeBiwpT1eZOwB7Vt9_gK2LiMHaFtkM0w91ACePONVPmQ@mail.example.com, 
   mail_id: 1wR6qb-51v7G, Hits: -, size: 1944, dkim_sd=20120113:example.com, 590 ms

Errors

(!)ClamAV-clamd av-scanner FAILED:… lstat() failed: Permission denied. ERROR

Add the user clamav to the group amavis.

   usermod --groups amavis clamav

Then add this to /etc/amavisd.conf

   AllowSupplementaryGroups yes

This might help also

   chmod -R 775 /var/amavis/tmp