Mal/Packer is a program that has been packed with a protection system typically used by malware authors.
Mal/Packer has been used in many malware families such as the following:
parasitic viruses (for example members of W32/Looked-Gen)
mass-mailing worms (for example members of W32/Mytob-Fam)
network worms with IRC backdoor functionality (for example members of W32/Rbot-Fam)
phishing Trojans (for example members of Troj/Banker-Fam)
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