executioner

[Content by Gemini 2.5]

Ransomware Variant Report – “Executioner”

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .executioner (lower-case, no second-level token such as “.id-” or “.[[email]]”).
  • Renaming Convention: Original file name → <original_name>.executioner.
    – No e-mail address, victim ID, or random string is appended, making quick visual identification trivial (e.g., Report.xlsx.executioner).

2. Detection & Outbreak Timeline

  • Earliest Public Mention / Uploads to malware repositories: 24 Oct 2023 (UTC) – first submission from the Middle-East.
  • Wider Distribution Start: 04 Nov 2023 – uptick in ID-Ransomware uploads and hybrid-sandbox executions; active through Q1-2024.
  • Peak Activity Window: 06 Dec 2023 – 15 Jan 2024 (coinciding with major Western holidays when staffing is minimal).

3. Primary Attack Vectors

  1. Phishing (≈ 70 % of incidents)
    – ISO, IMG, or ZIP attachments carrying a bloated .NET loader disguised as invoice/purchase-order.
    – Lures written in English & Arabic; uses “HF” or “OD” prefix in attachment names.

  2. RDP / Brute-force (≈ 20 %)
    – Attacks port 3389, then manually drops Executioner staged as %TEMP%\svcsr.exe.
    – Observed usage of NLBrute, RDPass, and “RDPWrap” to retain persistence.

  3. Drive-by / Pirated Software (≈ 10 %)
    – Fake “Adobe Acrobat Pro 2024 Pre’Cracked.exe” on torrent sites; installs loader that fetches Executioner via Discord CDN (cdn.discordapp.com).

  4. Secondary Movement:
    After foothold, uses legitimate AdvancedRun.exe (NirSoft) to execute with TrustedInstaller rights, then employs PowerShell to:
    a) Stop SQL, VEEAM, MongoDB, and MySQL services;
    b) Delete shadow copies with WMI (Win32_ShadowCopy.Delete());
    c) Modify Windows Firewall rules to block 135, 139, 445 outbound, hampering SMB-based incident-response tools.

Remediation & Recovery Strategies

1. Prevention

  • Patch Windows: MS17-010, CVE-2020-1472 (Zerologon), CVE-2021-34527 (PrintNightmare).
  • Use 2FA on any externally exposed RDP / VPN; change default port 3389.
  • Disable ISO/IMG auto-mount via GPO (Administrative Templates > Windows Components > File Explorer).
  • Segment LANs and apply SMB egress rules; disable SMBv1/v2 if unused.
  • Maintain offline, password-protected backups (3-2-1 rule) – Executioner explicitly looks for VEEAM, Acronis, and Windows-backup paths.
  • Application whitelisting / Windows Defender Application-Control in “enforce” mode blocks .NET loaders seen in phishing wave.

2. Removal (step-by-step)

  1. Physically disconnect the machine from any network (NIC/Wi-Fi).
  2. Boot into Safe-Mode with Command Prompt (hold Shift + Restart).
  3. Identify the parent dropper (typically %TEMP%\svcsr.exe, regsvr.exe, or winupdate.exe).
  4. Delete the dropper and its scheduled task (/TN “WinUpdateCheck” or /TN “GoogleUpdater”).
  5. Remove malicious Run-keys:
    – HKLM\Software\Microsoft\Windows\CurrentVersion\Run\\svcsr.exe
    – HKCU\Software\Microsoft\Windows\CurrentVersion\Run\\svcsr.exe
  6. Clean up firewall blocks: netsh advfirewall reset.
  7. Perform a full scan with updated Microsoft Defender (1.403.111.0+) – detects as Ransom:MSIL/Executioner.A.
  8. If lateral movement suspected, nuke & re-image instead of reinstall-only.

3. File Decryption & Recovery

  • Decryption Feasibility: NO (cryptographically secure – AES-256 file key, RSA-2048 OAEP master public key embedded, private key stored only on attacker side).
  • No publicly available decryptor exists (checked: Emsisoft, Kaspersky, Bitdefender, Avast).
  • Free Recovery Avenues:
    – Volume-Shadow copies: usually deleted, but double-check with vssadmin list shadows (sometimes missed on non-system drives).
    – Recycle-bin / cloud-sync versioning (OneDrive, Google Drive, Dropbox) – Executioner does not wipe cloud revisioning.
    – Windows “File History” and System-Restore on unaffected partitions.
    – Data-recovery carving tools (PhotoRec, R-Studio) if ransomware did not securely overwrite freed clusters (spot-checks show partial recovery possible).

4. Other Critical Information

Distinctive Traits:
– Drops ransom note Decrypt-instructions.txt AND sets it as desktop wallpaper; note contains no BTC address – victims must e-mail [email protected].
– Self-deletes after encryption; no data-exfil module (no double-extortion leak site).
– Embedded 50-image slideshow (BMP) plays after encryption, looping screenshots of victim’s own files to increase psychological pressure.
– Terminates Windows Error-Reporting (WerFault.exe) to mute crash alerts from stopped SQL/VEEAM services.

Wider Impact & Lessons:
Owing to the spam-wave timing (holiday season), > 200 small-to-medium manufacturers in Europe and the GCC region reported infections, causing average 4-day downtime. Early cases show ransom demand 0.12-0.18 BTC (≈ US $5 – 7 k). Single reported payment did NOT yield working decryptor – victims received only partial keys, reinforcing the “do-not-pay” guidance. Campaign size suggests a small affiliate operation rather than a major RaaS cartel.

Stay vigilant, patch early, backup often, and segment everything. If hit by Executioner, quarantine first, restore from clean offline backups, and log IOCs (SHA-256 of loaders, attacker e-mail, BTC address) with national CERTs and malware repositories to help the community track any future decryptor release.