If an anti-virus program is running on the Discover target (repository), and it detects a virus within a confidential file that violates a detection policy, the AV solution may quarantine the file before Vontu sends the file through to detection. In this case, does Vontu create an incident?
It is recommended that anti-virus software be installed in a location other than the Vontu folders of a detection server. See KB 41984: Anti-Virus Software Can Cause a Vontu Shutdown
Once file contents are opened and inspected, it is unlikely that the "cracked virus" would trigger AV detection. If an AV product is running on the target server, the file will most likely be blocked and recorded as an "unprocessable item".