Packed.Cupx!gen3 is a heuristic detection for files that may have been obfuscated or encrypted in order to conceal them from antivirus software.
This heuristic detection is used to detect threats associated with the following families:
Files that are detected as Packed.Cupx!gen3 are considered malicious. We suggest that any files you believe are incorrectly detected as Packed.Cupx!gen3 be submitted to Symantec Security Response. For instructions on how to do this using Scan and Deliver, read Submit Virus Samples
Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":