LockBit 3.0: Forensic Reverse-Engineering & Architectural Dossier

LockBit 3.0 (internal project designation LockBit Black) is a modular ransomware platform written in C and assembly. The architecture incorporates code elements from BlackMatter and DarkSide, utilizing runtime API hash resolution, a mandatory command-line decryption passkey (-pass) to decrypt in-memory code sections, an asynchronous multi-threaded IOCP file processing engine, and dual cryptographic algorithms (ChaCha20/AES-GCM with Curve25519/RSA-4096).

{
  "-pass": "Mandatory 32-character hexadecimal key used to decrypt code segments and configuration table in memory. Execution terminates if omitted.",
  "-k": "Path to local key escrow file containing session encryption keys.",
  "-path": "Directs encryption strictly to the designated folder path, suppressing full-drive traversal.",
  "-p": "Alternative parameter syntax to target a single directory or network mount.",
  "-n": "Disables network share discovery and enumeration via WNetOpenEnumW and NetShareEnum.",
  "-log": "Directs forensic execution trace and encrypted file paths to a local log file.",
  "-safe": "Configures bcdedit safeboot network and schedules service to execute payload upon Safe Mode reboot.",
  "-silent": "Runs headless without console output or UI dialog allocations."
}

{
  "description": "Encrypted binary structure within .data section, decrypted via custom XOR/RC4 loop keyed by -pass parameter",
  "fields": [
    "0x00: 4-byte CRC32 checksum of decrypted configuration data",
    "0x04: 32-byte master Curve25519 public key (or 512-byte RSA-4096 public key modulus)",
    "0x24: 16-byte unique affiliate identification token",
    "0x34: Boolean flags bitmap (enable_network_shares, enable_safe_mode, kill_processes, kill_services, wipe_shadows)",
    "0x38: Offset to null-delimited process termination blacklist (sqlservr.exe, excel.exe, winword.exe, etc.)",
    "0x3C: Offset to null-delimited service termination blacklist (vss, msexchange, sql, veeam, sophos, backup)",
    "0x40: Offset to directory exclusion list (Windows, ProgramData, System Volume Information, $Recycle.Bin)",
    "0x44: Offset to file extension exclusion list (.exe, .dll, .sys, .lnk, .lockbit)",
    "0x48: Offset to ransom note template string (incorporating dynamic affiliate Tor URL and personal ID)",
    "0x4C: Desktop wallpaper BMP payload byte stream"
  ]
}

{
  "initialization": "Validates command-line arguments. Locates -pass flag and derives runtime decryption key. Decrypts internal API resolution hashes and executes dynamic PE loader.",
  "antiAnalysis": "Executes CPUID instruction to detect hypervisor bit. Invokes NtSetInformationThread(ThreadHideFromDebugger). Checks PEB.BeingDebugged and performs timing verification via rdtsc.",
  "tokenElevation": "Invokes OpenProcessToken to acquire SeDebugPrivilege, SeTakeOwnershipPrivilege, and SeBackupPrivilege. If running with unprivileged token, spawns ICMLuaUtil COM elevation helper.",
  "serviceAndProcessSweeper": "Iterates through Service Control Manager using EnumServicesStatusExW; calls ControlService(SERVICE_CONTROL_STOP) on identified backup/security services. Uses CreateToolhelp32Snapshot to identify and TerminateProcess file-locking processes.",
  "shadowCopyPurge": "Invokes IVssBackupComponents COM interface to locate and delete all active volume shadow copies. Executes fallback shell commands: vssadmin delete shadows /all /quiet and bcdedit /set {default} recoveryenabled no.",
  "encryptionPipeline": "Initializes Windows I/O Completion Port (IOCP). Traverses drive volumes and network shares. Workers pop file paths, generate 256-bit ChaCha20 session keys, perform full or intermittent stride encryption, append Curve25519-wrapped key header, and rename file to .[random_affiliate_id].",
  "ransomDelivery": "Drops ransom note README.txt across all traversed directories. Writes BMP wallpaper to %TEMP% and updates desktop via SystemParametersInfoW(SPI_SETDESKWALLPAPER). Triggers network printer spooling via EnumPrintersW and StartDocPrinterW."
}

Concrete technical breakdown of functional modules implemented in the LockBit 3.0 binary:

Decentralized command infrastructure operating over Tor V3 Onion hidden services. Communication routing occurs via embedded SOCKS5 proxy components connecting to preconfigured Tor gateway nodes. Operators interact with affiliates via Tox decentralized protocol IDs embedded within the configuration structure. Negotiation and ransom verification proceed through dedicated per-victim Tor Onion portals authenticated via unique victim identification tokens.

Indicators of compromise and forensic patterns recorded across laboratory triage: