Threat Signal Report

APT Billbug Victimized Asian Certification Authority and Government Agencies

description-logo Description

FortiGuard Labs is aware of a report that APT group "Billbug" compromised a certificate authority (CA) as well as multiple government and defense organizations in Asia. Also known as Lotus Blossom and Thrip, the APT group reportedly has been active since 2009 and uses custom backdoor malware "Hannotog" and "Sagerunex" as well as available tools in compromised machines.

Why is this Significant?

This is significant because Billbug APT threat actor group targeted a certificate authority (CA). Should digital certificates be compromised, the attacker could use them to sign malware for detection evasion by security solutions and eavesdrop on HTTPS communications.

Also, the reports indicate that multiple organizations in government and defense sectors in Asia were compromised by Billbug APT.

What is Billbug APT?

Billbug, Lotus Blossom and Thrip, is a threat actor that has been reportedly active since at last 2009 and has interests in U.S. organizations as well as government, defense, and communications organizations in Southeast Asia. Their primary motive is thought to be information espionage.

Billbug APT employs living-off-the-land techniques and uses custom malware. The tools that were reportedly used by Billbug APT are the following:

  • Hannotog backdoor
  • Sagerunex backdoor
  • AdFind
  • Certutil
  • LogMeIn
  • Mimikatz
  • NBTscan
  • Ping
  • Port Scanner
  • PowerShell
  • PsExec
  • Route
  • Tracert
  • Winmail
  • WinRAR
  • WinSCP

What is the Status of Coverage?

FortiGuard Labs detects the files in the report with the following AV signatures:

  • W32/Agent.QTP!tr
  • W32/Elsentric.J!tr
  • W32/Generic.A!tr
  • W32/PossibleThreat
  • W64/Agentb.F!tr
  • W64/Agent.LF!tr
  • W64/Elsentric.E!tr
  • W64/Elsentric.G!tr
  • Malicious_Behavior.SB
  • PossibleThreat.PALLAS.H
  • Riskware/Kryptik


Traffic Light Protocol

Color When Should it Be used? How may it be shared?


Not for disclosure, restricted to participants only.
Sources may use TLP:RED when information cannot be effectively acted upon by additional parties, and could lead to impacts on a party's privacy, reputation, or operations if misused. Recipients may not share TLP:RED information with any parties outside of the specific exchange, meeting, or conversation in which it was originally disclosed. In the context of a meeting, for example, TLP:RED information is limited to those present at the meeting. In most circumstances, TLP:RED should be exchanged verbally or in person.


Limited disclosure, restricted to participants’ organizations.
Sources may use TLP:AMBER when information requires support to be effectively acted upon, yet carries risks to privacy, reputation, or operations if shared outside of the organizations involved. Recipients may only share TLP:AMBER information with members of their own organization, and with clients or customers who need to know the information to protect themselves or prevent further harm. Sources are at liberty to specify additional intended limits of the sharing: these must be adhered to.


Limited disclosure, restricted to the community.
Sources may use TLP:GREEN when information is useful for the awareness of all participating organizations as well as with peers within the broader community or sector. Recipients may share TLP:GREEN information with peers and partner organizations within their sector or community, but not via publicly accessible channels. Information in this category can be circulated widely within a particular community. TLP:GREEN information may not be released outside of the community.


Disclosure is not limited.
Sources may use TLP:WHITE when information carries minimal or no foreseeable risk of misuse, in accordance with applicable rules and procedures for public release. Subject to standard copyright rules, TLP:WHITE information may be distributed without restriction.