IcedID Banking Trojan Teams up with Ursnif/Dreambot for Distribution

Update: 4/11 we have corrected the detection to Ursnif/Dreambot

This post was authored by Ross Gibb with research contributions from Daphne Galme, and Michael Gorelik of Morphisec, a Cisco Security Technical Alliance partner.

Cisco has noticed an increase in infections by the banking trojan IcedID through our Advanced Malware Protection (AMP) system. Security researchers first reported a new banking Trojan known as “IcedID” [1] in November 2017. At the time of discovery, IcedID was being distributed by Emotet, another well-known banking trojan malware. In late February and throughout March 2018, we noticed an increase in infections from IcedID being detected throughout the AMP ecosystem. Like in November 2017, some of the infections could be traced to Emotet, but this time, many detections could instead be traced to emails with attached malicious Microsoft Word documents containing macros. When the malicious documents are opened and the macros are enabled, Ursnif/Dreambot, another trojan, would be downloaded and executed, which subsequently downloads IcedID. In addition to Ursnif/Dreambot, many of the samples downloaded a second payload, a Bytecoin miner (Bytecoin is a crypto currency similar to bitcoin).