The remote host is missing a critical security patch or upgrade.
The remote client is running the Avira Anti-Virus engine. This version of the Avira scan engine is vulnerable to a flaw wherein attackers can bypass the scan engine by submitting specially formatted 'ZIP', 'CAB', 'RAR', or 'LH' files. An attacer, exploiting this flaw, would be able to pass malicious code through the scan engine.
Upgrade to Avira scan engine 18.104.22.168/22.214.171.124 or later.