Antivirus vendor BitDefender reports they have detected the first trojan using Sony DRM to hide. The trojan named Backdoor.IRC.Snyd.A by Bit Defender, also dubbed Backdoor.Win32.Breplibot.b (Kaspersky) Troj/Stinx-E (Sophos) W32/Brepibot virus (McAfee) is essentially impossible for a normal user to detect when hidden by Sony DRM software.
The technical analysis can be read here. A detection and removal tool will be available from BitDefender within a few hours.