Into The Silent Night

  • Yuta Sawabe NTT Security Holdings
  • Ryuichi Tanabe NTT Security Holdings
  • Fumio Ozawa NTT Security Holdings
  • Rintaro Koike NTT Security Holdings
Keywords: Banking Trojan, Zloader, Botnet Tracking, System Development


Since the birth of Zeus family malwares, they have been sharpening their edge. Zloader is one of the active variants among Zeus family malwares. In December 2019, Zloader revived as “Silent Night.” It communicates with C&C servers using DGA (Domain Generation Algorithm), because changing C&C servers’ domain names can bypass malware detection systems. As a result, it makes it easier to steal information from infected hosts. This study proposes a system that traces Zloader’s C&C servers automatically. This system collects samples, analyzes configuration data, and calculates DGA domains. Moreover, the system collects log files that store information about the infected hosts on the attackers’ servers. The system can not only generate threat intelligence about Zloader for SOC and CSIRT but also follow the trend of attack campaigns. Furthermore, we will discuss how attackers acquire the DGA domains tactically.


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Hatching Triage.