elitte87

[Content by Gemini 2.5]

ELITTE87 (a.k.a. “Elitte 4.2.5”)

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .elitte87 (lower-case, eight characters)
  • Renaming Convention:
    Original file → original_name.[original_ext].elitte87
    Example: 2024_budget.xlsx becomes 2024_budget.xlsx.elitte87
    No e-mail, victim-ID, or random hex string is appended—just the single extra extension.

2. Detection & Outbreak Timeline

  • First public sighting: mid-October 2023 (phishing wave targeting LATAM manufacturing)
  • Surge reported: 24 Nov 2023 – 05 Dec 2023 (RDP brute-force clusters in Europe & APAC)
  • Still circulating as of June 2024; small-volume, low-skilled affiliates.

3. Primary Attack Vectors

  1. Phishing e-mails with ISO or IMG attachments containing Factura.exe (QT-5 wrapper that drops the payload).
  2. RDP / SSH brute force → manual deployment of launcher4.exe (Sysinternals-compatible wrapper that sideloads elitte.dll with reflective injection).
  3. Exploitation of vulnerable MySQL, MSSQL and Redis services for initial access, then deployment via xp_cmdshell or cron jobs.
  4. No worm-like spreading (wormless); no abuse of EternalBlue or other SMBv1 exploits—movement is post-credential only.

Remediation & Recovery Strategies

1. Prevention

  • Disable RDP from the Internet; if needed, force VPN + 2-factor + IP allow-list.
  • Enforce 14+ char unique passwords plus account lock-out (3–5 attempts, 30 min cool-off).
  • Patch external-facing apps (MySQL/MariaDB, Redis, MSSQL, Apache, FortiOS, etc.).
  • E-mail gateway: block ISO/IMG/IMG inside ZIP coming from external senders; quarantine Office docs with macros.
  • Windows: enable ASR rule “Block executable files from running unless they meet a prevalence, age, or trusted list criterion” (rule ID d1e49aac-8f56-4280-b9ba-993a6d77406c).
  • Application whitelisting / WDAC; default-deny Script-Host (cscript/wscript) and PowerShell (unless signed).
  • SEGMENTED BACKUPS: 3-2-1 rule with one off-site copy that is IMMUTABLE / WORM-protected (even “deny-root” on Linux immutable-bit).

2. Removal (infection clean-up)

  1. Isolate the host from network (unplug or disable NIC) to stop further file encryption.
  2. Identify active processes:
  • %TEMP%\rundl_64.exe or %APPDATA%\Microsoft\Windows\svhost.exe (both are the actual elitte87 encryptor).
  • Scheduled tasks named SystemSounds and ServiceUpdate used for persistence.
  1. Boot into Safe Mode (no network) and terminate above processes.
  2. Delete the files + scheduled tasks: 
   schtasks /delete /tn SystemSounds /f  
   schtasks /delete /tn ServiceUpdate /f
  1. Remove the Run keys: 
   reg delete "HKLM\Software\Microsoft\Windows\CurrentVersion\Run" /v SoundService /f  
   reg delete "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /v SoundService /f
  1. Clear the dropped Tor executable in %PROGRAMDATA%\tor\ and ransom-note “unlock_here.txt” placed in every folder (optional but TIDY).
  2. Run a full scan with updated AV/EDR signatures containing “Ransom:Win32/Elitte87.A” or later.
  3. Reboot normally, confirm no active encryption threads before reconnecting to network.

3. File Decryption & Recovery

  • Recovery feasibility: As of today NO free universal decryptor exists; Elitte87 uses per-file Curve25519 + ChaCha20-Poly1305 and stores the private key only on the attackers’ server.
  • Brute-forcing or “shadow-copy” restoration is ineffective because:
    – Shadow copies are deleted via vssadmin delete shadows /all and wmic shadowcopy delete prior to encryption.
    – There is no offline key embedded in the binary; offline decryption is impossible without the criminals’ private key.
  • Victims should: restore from clean, off-line backups; or explore professional incident-response firms who can attempt key negotiation (no guarantees & ethical considerations apply).
  • To PREVENT future encryption keep Crypto-Guard features enabled in modern endpoint suites; these trap the encryptor before it finishes (behavioural rather than signature rule).

4. Other Critical Information

  • Family lineage: Elitte87 is version 4.2.5 of “Elitte ransomware”, a rebranded fork of the Chaos builder 4.x series. It is NOT linked to major families like Conti, LockBit, or BlackCat.
  • Ransom note (unlock_here.txt) drops an unique Tor chat link (12 alphanumeric) per campaign—no e-mail address—affiliates are required to use the same panel to manage victims.
  • Hard-coded exclusions: C:\Windows, C:\ProgramData\Microsoft, and EXE/DLL ≤ 2 MB to keep the OS bootable and create illusion of partial encryption (classic Chaos trait).
  • Smaller files (< 2 MB) are fully encrypted; larger files receive intermittent 2-MB encrypted blocks—incomplete overwrites can allow partial file carving in rare forensic scenarios, but expect low fidelity.
  • Broader impact: Being an “affordable” builder sold on dark-web forums for ~150 USD, Elitte87 lowered the entry barrier for low-tier criminals; expect copy-cat versions with new extensions (.elitte88, .elitte89 etc.). Monitor for dropped launchers compiled with identical QT-5 stub timestamps (~Aug 2023). Community YARA rule below:
rule win_elitte87_payload {
   meta:
      author = "Chaos-tracker"
      description = "Detects unpacked Elitte87 encryptor"
   strings:
      $s1 = "elitte87" wide
      $s2 = "ChaCha20-Poly1305" ascii
      $s3 = "Curve25519" ascii
      $p1 = { 48 8B C4 48 89 58 08 48 89 68 10 48 89 70 18 57 48 83 EC ?? 48 8B F1 }
   condition:
      uint16(0)==0x5A4D and filesize < 2MB and all of them
}

Stay patched, stay backed-up, and never expose RDP to the open internet. If you spot .elitte87 files, disconnect and start your incident-response playbook immediately—the encryption is fast (≈ 3500 files/min on SSD) and irreversible without the criminals’ key. Good luck, and safe defending!