Trojan.Cryptolocker!g2 is a heuristic detection used to detect threats associated with the Trojan.Cryptolocker family of threats.
Virus definitions dated November 13, 2013 or earlier may detect this threat as Trojan.Ransomcrypt!g4.
For more information, please see the following resource:
Cryptolocker: A Thriving Menace
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