W32/BlackCat.A!tr.ransom

description-logoAnalysis

W32/BlackCat.A!tr.ransom is a generic detection for a trojan.
Since this is a generic detection, malware that are detected as W32/BlackCat.A!tr.ransom may have varying behaviour.
Below are some of its observed characteristics/behaviours:

  • This malware is known as BlackCat/ALPHV ransomware. BlackCat is a ransomware-as-a-service (RaaS) model which recruits affiliates to help carry out attacks. It is coded in rust, which allows for customization to help individualize the attacks.

  • Upon execution, the ransomware will attempt to delete shadow volume copies, clear the recycle bin, disable recovery mode, clear event logs, and kill various processes and services, before encrypting the victim's data.

  • The encrypted files will be appended with a random extension, as referenced in the dropped ransom note, "RECOVER-[extension]-FILES.txt". The ransom note informs the victim of the encrypted files and lists the type of data that was stolen. It will direct the victim to a TOR site for payment to recover the files and threatens to publish the stolen data if the attacker's demands are not met. Affected users are discouraged on taking this action as it does not guarantee the retrieval of data upon payment. Depending on the affiliate, the ransomware can also be customized to self propogate, set the wallpaper, kill VM's and delete snapshots.

  • This malware has been associated with the following third party article/advisory.
  • https://www.ic3.gov/Media/News/2022/220420.pdf
    
    The correlation has been established due to a database near/exact match on one of the sample/IOC/file hash indicated in the mentioned resource.

  • Below are images of the malware:

    • Figure 1: List of services and processes killed.


    • Figure 2: Contents of ransom note.


    • Figure 3: TOR site with published data for download.


  • Below are some of the sites associated with the ransomware:
    • http://alphvmmm27o3abo3r2mlmjrpdmzl[removed]c9918c7efeb
    • http://sty5r4hhb5oihbq2mwe[removed]
    • http://y4722ss6[removed]
    • http://id7[removed]dckaux3uvjc7l7xrsiqad.onion[removed]
    • http://aoczpp[removed]wrfumxslx3vyd.oni[removed]

  • Following are some of the near/exact IOCs/file hash associated with this detection:
    • Md5: 817f4bf0b4d0fc327fdfc21efacddaee
      Sha256: f837f1cd60e9941aa60f7be50a8f2aaaac380f560db8ee001408f35c1b7a97cb
    • Md5: 173c4085c23080d9fb19280cc507d28d
      Sha256: 731adcf2d7fb61a8335e23dbee2436249e5d5753977ec465754c6b699e9bf161
    • Md5: a854c960cde68d43fd42a24e79587b28
      Sha256: bd337d4e83ab1c2cacb43e4569f977d188f1bb7c7a077026304bf186d49d4117
    • Md5: 81d7c2d1dca5da7eef2896a76768d142
      Sha256: 7b2449bb8be1b37a9d580c2592a67a759a3116fe640041d0f36dc93ca3db4487
    • Md5: c1dd3d5a3528bf56632200d247ca9774
      Sha256: 15b57c1b68cd6ce3c161042e0f3be9f32d78151fe95461eedc59a79fc222c7ed

recommended-action-logoRecommended Action

  • Make sure that your FortiGate/FortiClient system is using the latest AV database.
  • Quarantine/delete files that are detected and replace infected files with clean backup copies.

Telemetry logoTelemetry

Detection Availability

FortiGate
FortiClient
FortiAPS
FortiAPU
FortiMail
FortiSandbox
FortiWeb
Web Application Firewall
FortiIsolator
FortiDeceptor
FortiEDR

Version Updates

Date Version Detail
2023-05-23 91.03526
2023-04-10 91.02232
2023-02-28 91.01002
2023-02-27 91.00982
2023-01-31 91.00154
2023-01-19 90.09802
2023-01-03 90.09317
2022-12-20 90.08897
2022-12-09 90.08584
2022-11-29 90.08277