Dark Web Profile: Brain Cipher – SOCRadar® Cyber Intelligence Inc.

The Brain Cipher ransomware attack targeted Indonesia’s National Data Center (PDN), encrypting government servers and disrupting immigration and other services across more than 200 agencies. The operation appears tied to a broader ecosystem using LockBit’s leaked builder, with the group later apologizing and offering a decryption tool, while the deeper mechanics and indicators are documented by researchers. Hashtags: #BrainCipher #LockBit

Keypoints

  • Brain Cipher executed a high-profile ransomware attack against Indonesia’s National Data Center (PDN), impacting immigration services and other government online functions.
  • The group leverages LockBit’s leaked builder (LockBit 3.0) to create ransomware components, adjusting the config to tailor the encryptor and C2 server settings.
  • Initial ransom demand reached $8,000,000, but Brain Cipher apologized to Indonesia on July 2, 2024, and promised a free decryption tool with optional donation via a Monero wallet.
  • Brain Cipher’s attacks exhibit classic ransomware behavior: file encryption with a distinctive extension, encryption of numerous files, and attempted data impact alongside extortion.
  • Defensive researchers note strong evasion and anti-analysis tactics, including self-deletion, process/Browser data modification, and code obfuscation (e.g., a specific obfuscation sequence).
  • Key indicators include specific Brain Cipher sample hashes, onion-based data-leak site links, and public contact/communication channels; some infrastructure details (C2) are configurable via the builder’s config.json.

MITRE Techniques

  • [T1486] Data Encrypted for Impact – “Brain Cipher is a variant of the LockBit ransomware family. It is designed to encrypt files on compromised systems, append a distinctive file extension, and demand a ransom payment for decryption.”
  • [T1070.004] File Deletion – “Upon execution, Brain Cipher immediately deletes itself to hinder forensic analysis and detection.”
  • [T1027] Obfuscated/Encrypted Files or Information – “The obfuscation technique used… involves the instruction sequence push FFFFFF9Ch; retf.”
  • [T1564.001] Hide Artifacts: Hide Thread/Debugger Evasion – “hides threads from debuggers and executes in a suspended mode to avoid detection.”
  • [T1071] Command and Control – “it can specify the command and control server” within its builder configuration (config.json).
  • [T1190] Exploit Public-Facing Application – “initial access vectors, such as vulnerability exploitation” mentioned as a possible vector.
  • [T1566.002] Spearphishing Link – “initial access vectors… a spear-phishing operation.”

Indicators of Compromise

  • [Hash] MD5, SHA1, SHA256 – 448f1796fe8de02194b21c0715e0a5f6, 935c0b398373f8c5e8ef03c92d606c72c44f49b8, eb82946fa0de273dbaaaef320e8925d9a8cc5b7e839e97e2982a1d18ba43c1a4 – Brain Cipher sample 9gGB296kd4.exe (associated with the LockBit family)
  • [File] 9gGB296kd4.exe – Brain Cipher sample filename associated with the LockBit lineage
  • [Hash] – Additional Brain Cipher hashes referenced: 0ed5729655b3f09c29878e1cc10de55e0cbfae7ac344f574d471827c256cf086, 6e07da23603fbe5b26755df5b8fec19cadf1f7001b1558ea4f12e20271263417
  • [URL] Onion-based Data Leak Site: http://vkvsgl7lhipjirmz6j5ubp3w3bwvxgcdbpi3fsbqngfynetqtw4w5hyd[.]onion/ and Communication for victims: http://mybmtbgd7aprdnw2ekxht5qap5daam2wch25coqerrq2zdioanob34ad[.]onion/
  • [Wallet] Bitcoin: bc1qqjzd8jrcvz5tl895uvgy6ph83g7sh06uzu6vn8 – mentioned as a payment channel; Monero wallet noted for donations but address not disclosed

Read more: https://socradar.io/dark-web-profile-brain-cipher/