Threat Signal Report
Joint Cybersecurity Advisory on Zeppelin Ransomware (AA22-223A)
On August 11, 2022, the Federal Bureau of Investigation (FBI) and the Cybersecurity and Infrastructure Security Agency (CISA) released a joint advisory on Zeppelin ransomware. The alert provides insight into the tactics, techniques, and procedures (TTPs) along with indicators of compromise used by Zeppelin threat actors. Zeppelin has been operating since 2019 and has targeted organizations across multiple industries as well as critical infrastructure sectors.
What is Zeppelin ransomware?
Zeppelin is a Delphi-based ransomware and is run as a Ransomware-as-a-Service (RaaS). First reports of Zeppelin ransomware goes back as far as December 2019. Some reports suggest that Zeppelin ransomware originates from the Vegaslocker and Buran strains.
According to the CISA advisory, Zeppelin ransomware's infection vectors include RDP exploitation, leveraging vulnerabilities in popular FireWall products and phishing emails. Once a threat actor compromises the victim's network, it steals sensitive information from the victim before starting the file encryption process. Zeppelin ransomware typically adds a ".zeppelin" file extension to the affected files, however other files extensions used were observed. After files are encrypted, the victim is presented with a ransom note that is typically named "!!! ALL YOUR FILES ARE ENCRYPTED !!!.TXT" containing attacker's contact information (email, Jabber, ICQ or Telegram) as well as a ransom message. Zeppelin victims are threatened that encrypted files will not be recovered, and stolen information will be released to the public if the ransom is not paid.
Ransom note from a recent Zeppelin ransomware sample
The advisory also states that threat actors ran Zeppelin ransomware more than once on the compromised network in some cases, which resulted in multiple decryption keys being required for file decryption.
What is the Status of Coverage?
FortiGuard Labs provides the following AV coverage against known Zeppelin ransomware variants:
Traffic Light Protocol
|Color||When Should it Be used?||How may it be shared?|
TLP: REDNot 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.|
TLP: AMBERLimited 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.|
TLP: GREENLimited 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.|
TLP: WHITEDisclosure 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.|