BlackCat Ransomware | Highly-Configurable, Rust-Driven RaaS On The Prowl For Victims

BlackCat is a Rust-based RaaS that targets Windows and Linux with configurable encryption and extortion features, delivering payloads via third-party frameworks or exposed apps and demanding high ransoms. It markets affiliates on underground forums, maintains a victim blog, and uses a TOR-based portal for data leakage negotiations, underscoring a highly configurable and stealthy approach. #BlackCat #AlphaVM #AlphaV #Rust #RaaS #CobaltStrike #Tor

Keypoints

  • BlackCat is a Rust-written ransomware-as-a-service (RaaS) that targets Windows and Linux, with ransom demands in the hundreds of thousands to millions of dollars.
  • Delivery relies on 3rd-party frameworks like Cobalt Strike or exposed vulnerable applications, with operators maintaining a victim blog to publish leaked data if victims don’t cooperate.
  • Samples require an “access token” as a parameter at execution, an anti-analysis feature that can be bypassed by using any string as the token.
  • The ransomware offers a visible command set and verbose mode; it includes VMware-centric commands and can terminate processes/services to enable encryption.
  • Encryption uses ChaCha20 and AES; file extensions vary by sample, and a ransom note plus TOR-based payment portal are used for extortion and data leakage threats.
  • Post-infection activity includes VSS deletion on Windows, drive enumeration, privilege escalation, and configurable exclusions and kill lists for processes/services.

MITRE Techniques

  • [T1027.002] Obfuscated Files or Information – Software Packing – Used to hinder analysis; “Samples analyzed (to date ) require an “access token” to be supplied as a parameter upon execution. This is similar to threats like Egregor, and is often used as an anti-analysis tactic.”
  • [T1027] Obfuscated Files or Information – The malware relies on obfuscation/packing as part of its delivery and operation; “Third-party framework/toolset (e.g., Cobalt Strike) or via exposed (and vulnerable) applications.”
  • [T1007] System Service Discovery – “The targeted processes and services are noted in the kill_processes and kill_services sections respectively.”
  • [T1059] Command and Scripting Interpreter – “The executable payloads support a variety of commands, many of which are VMware-centric. WMIC.exe (CLI interpreter) …”
  • [TA0010] Exfiltration – “Infected uses are instructed to connect to the attackers’ payment portal via TOR.”
  • [T1082] System Information Discovery – “querying for the system UUID (wmic).” and related startup checks.
  • [T1490] Inhibit System Recovery – “vssadmin.exe delete shadows /all /quiet.”
  • [T1485] Data Destruction – “Data encryption and destruction are part of the impact.” and “The ransomware encrypts files.”
  • [T1078] Valid Accounts – “Samples analyzed require an ‘access token’ to be supplied as a parameter…”
  • [T1486] Data Encrypted For Impact – “The ransomware supports both ChaCha20 and AES encryption schemes.”
  • [T1140] Encode/Decode Files or Information – Indirectly evidenced by the file encryption process and extensions observed on encrypted files.
  • [T1202] Indirect Command Execution – “The payloads support a variety of commands… includes WMIC and cmd.exe.”
  • [T1543.003] Create or Modify System Process: Windows Service – The malware manipulates processes/services during kill lists and has Windows/Linux variants with system process considerations.
  • [T1550.002] Use Alternate Authentication Material: Pass the Hash – The access-token parameter indicates an authentication material used during execution.

Indicators of Compromise

  • [SHA256] Indicators of compromise – 0c6f444c6940a3688ffc6f8b9d5774c032e3551ebbccb64e4280ae7fc1fac479, 13828b390d5f58b002e808c2c4f02fdd920e236cc8015480fa33b6c1a9300e31
  • [SHA1] Indicators of compromise – 087497940a41d96e4e907b6dc92f75f4a38d861a, 11203786b17bb3873d46acae32a898c8dac09850

Read more: https://www.sentinelone.com/labs/blackcat-ransomware-highly-configurable-rust-driven-raas-on-the-prowl-for-victims/