A system and method for determining whether a packed executable is malware is presented. In operation, a malware evaluator intercepts incoming data directed to a computer. The malware evaluator evaluates the incoming data to determine whether the incoming data is a packed executable. If the incoming data is a packed executable, the malware evaluator passes the packed executable to an unpacking module. The unpacking module includes a set of unpacker modules for unpacking a packed executable of a particular type. The unpacking module selects an unpacker module according to the type of the packed executable, and executes the selected unpacker module. Executing the unpacker module generates an unpacked executable corresponding to the packed executable. The unpacked executable is returned to the malware evaluator where it is evaluated to determine whether the packed executable is malware.