Generating a set of attempted external contacts associated with a malware sample is disclosed. A malware sample is executed in an accelerated computing environment. In the accelerated computing environment, a guest time is advanced more quickly than a time by which a host time is advanced. A set of one or more attempted external contacts generated by the executing malware sample is recorded. The set of attempted external contacts includes at least one generated domain name. A remedial action is taken with respect to the generated domain name.