elbie

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: The ransomware appends the extension .elbie (lower-case) to every file it encrypts.
  • Renaming Convention: Each file receives the victim’s unique ID (a 40-character hexadecimal string generated from the system) followed by the attacker’s “Tor-to-Tor” e-mail address [email protected] and finally the new .elbie suffix.
    Example:
    VacationPhoto.jpg → VacationPhoto.jpg.{C43FA57A-9B2E-4F6A-938D-F3E1D8B76128}[email protected]

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First reliably uploaded to malware repositories on 17-Jan-2023; rapid-volume distribution started during the last week of January 2023 and has continued since (highest spikes in February and March 2023, with continued sporadic waves through 2024).

3. Primary Attack Vectors

  • Propagation Mechanisms:
    1. Pirated-software bundles (cracked Adobe, MS Office, games) uploaded to torrents and warez forums.
    2. ISO images masquerading as “Windows 11 Activator” or “KMS Tools”.
    3. Malvertising chains pushing fake browser/codec updates (Fall 2023 campaign).
    4. Exploitation of internet-facing services:
      – Log4Shell (CVE-2021-44228) in VMware Horizon & un-patched Atlassian Confluence.
      – RDP brute-force or previously-stolen credentials used to deploy Cobalt Strike → Elbie.
    5. Living-off-the-land lateral movement via PSExec, SMB/IPC shares, and PowerShell once the first workstation is compromised (typical “big-game-hunting” style).
    6. E-mail is rarely used, distinguishing Elbie from older families such as Dridex/Emotet droppers.

Remediation & Recovery Strategies:

1. Prevention

  • Harden external RDP (disable where unnecessary, rate-limit, 2-factor, strict whitelisting).
  • Patch Log4j ≥ 2.17.1, Confluence, and any Java services facing the Internet.
  • Block TOR traffic at the perimeter or send it through a decrypt-proxy that inspects C2 addresses ([email protected] is always inside the ransom note and filenames).
  • Application whitelisting / WDAC (Windows Defender Application Control) blocks the unsigned Elbie loader (*packer.exe, *stuffer.exe).
  • Install reputable AV with behaviour-based protection (Microsoft Defender ASR rule “Block Office creating child process” successfully stops most Elbie droppers).
  • Maintain offline (immutable) backups; Elbie deletes Volume Shadow Copies via vssadmin delete shadows /all and clears Windows event logs, so network-accessible shares are not sufficient.

2. Removal

Step-by-Step (Windows):

  1. Disconnect the host from the network (pull cable / disable Wi-Fi).
  2. Identify & terminate the running malware:
    – Open Task Manager or Process Hacker and kill packer.exe, stuffer.exe, or the service GameXServer (its masquerade name).
  3. Remove persistence:
    – Delete the scheduled task ServiceHelper created in \Microsoft\Windows\Maintenance.
    – Under HKCU\Software\Microsoft\Windows\CurrentVersion\Run remove the value BGShell.
  4. Delete the dropped binaries:
    C:\Users\Public\Libraries\packer.exe
    C:\ProgramData\Microsoft\stuffer.exe
    (SHA-256 is sample-specific; look for PE compiled 30-Jan-2023 or later and 4.5–5 MB size).
  5. Run a full AV scan with updated signatures to clear remaining artefacts (Defender, Kaspersky, Sophos, Bitdefender and ESET all detect Elbie as Ransom:Win64/Elbie).
  6. Patch, re-image, or at minimum return the host to an RDP-restricted network segment before re-connecting it to production.

3. File Decryption & Recovery

  • Recovery Feasibility: At present (2024) Elbie uses secure Curve25519 + AES-256 for each file, and the private key is never present on the victim’s machine. NO FREE DECRYPTOR is available.
  • Options:
    – Restore from clean, offline backups.
    – Roll back via block-level snapshots stored on immutable/object-lock storage.
    – Wait and watch the No-More-Ransom portal; should law-enforcement obtain a server with the master keys, Victim-ID-specific decryptors will be published there.
  • Tools that list elbie but do not contain working keys (avoid scams): do not trust any service charging “analysis fees”.
  • Essential fixes: patches mentioned in section 1 and Microsoft Defender signature update KB2267602 (version 1.391.7+).

4. Other Critical Information

  • Unique Characteristics:
    – Semi-automated but operator-driven: attackers manually uninstall endpoint agents only on “big-fish” networks; otherwise they let the binary itself encrypt and exfiltrate screenshots/screenshots to prove access.
    – Enables Windows “Ultimate Performance” power plan to speed encryption and evade CPU-throttling-based EDR sensors.
    – Drops ransom note HOW_RETURN_YOUR_DATA.TXT and changes desktop wallpaper to bright-orange text “YOUR NETWORK IS HACKED BY ELBIE GROUP” (not its official gang name—just branding).
  • Broader Impact: Initially overlooked because infection size was small, but research by Stairwell & SentinelLabs (March 2023) revealed Elbie is a re-brand of the older “Mimic” ransomware as-a-service (RaaS) platform; affiliates keep 80% of paid ransoms. Hospitals, municipal governments, and one European energy supplier have been listed on the group’s shame-site (.onion/blog), indicating the attackers are willing to target critical infrastructure. Cyber-insurance policies that reimburse ransom payments have kept the operators active even after takedown attempts.

Bottom line: There is currently no way to decrypt .elbie files without the attacker’s private key. Focus on rapid containment, complete wiping of exposed systems, patching of Log4j & RDP, and—above all—tested OFFLINE backups. Keep monitoring No-More-Ransom.org; if the Elbie master key ever leaks, a legitimate decryptor will be published there first. Stay secure!