deathhiddentear

# DeathHiddenTear (`deathhiddentear`) Ransomware Play-sheet

Technical Breakdown:

1. File Extension & Renaming Patterns

Confirmation of File Extension: .locked, .pabluk*/,.kimchenyn*/, and .deathhiddentear (the last one most common in recent campaigns).
Renaming Convention: Original name → [originalname].[originalextension].deathhiddentear
Example: Budget_2025.xlsx becomes Budget_2025.xlsx.deathhiddentear.

2. Detection & Outbreak Timeline

Approximate Start Date / Period:
Fork of the open-source Hidden Tear PoC (published 2015).
Active campaign windows observed:
• Wave #1 – Nov 2020 (Russian-language underground ads)
• Wave #2 – Jul 2022 (new .NET packer + obfuscator)
• Latest wave – Jan 2024 (distributed via cracked software & fake Zoom/Discord/Notion installers found on Pastebin links).

3. Primary Attack Vectors

| Mechanism | Details / CVE Usage |
|———–|———————|
| Phishing emails | ZIP/RAR attachments with .exe double-extension (proposal.pdf.scr, invoice-123.doc.exe). |
| Cracked software bundles | Adobe Acrobat, IDM, Autodesk, FL Studio, Malwarebytes “keygens.” |
| Malicious ads (malvertising) | Fake “Update Chrome” pop-up dropping MSI → Tojan dropper → DeathHiddenTear payload. |
| RDP / SMB brute-force | Uses ntlmrelayx or pass-the-hash to pivot; once on target it deletes VSS shadow copies with vssadmin delete shadows /all. |
| Software vulnerability exploitation | No significant exploit kits always tied, but DLL search-order hijacking abuses older MSBuild & MS Office builds. Rare EternalPrint exploits (CVE-2021-34527) in small-scale campaigns. |

Remediation & Recovery Strategies:

1. Prevention

| Control / Action | Description |
|——————|————-|
| Patch promptly | Prioritize Windows cumulative updates + browser, Office, RDP patches. |
| Disable remote .BAT, .CMD, .VBS file execution via email gateway rules (AV can still scan them). |
| Application allow-listing | Applocker / Microsoft Defender WDAC to block execution of %TEMP%\*, %APPDATA%\*\*.exe, and unsigned binaries. |
| Credential hygiene | 12+ char unique passwords for RDP; disable RDP from Internet via perimeter firewall and use VPN. |
| Logging & EDR | Deploy Microsoft Defender for Endpoint or open-source agents (Wazuh + Sysmon) to flag unusual command-line: vssadmin delete shadows, bcdedit /set bootstatuspolicy ignoreallfailures. |
| Backups | 3-2-1 rule (3 copies, 2 different media, 1 offline). Do not map backup drives as Windows drive letters. Use immutable object storage (e.g., S3 with Object Lock, Azure Blob with WORM).

2. Removal (Step-by-Step)

Isolate & Power-off network segments (pull cable first, investigate second).
Identify Patient-Zero & persistence – look in:
• HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
• %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup\*.exe – common persistence path: %APPDATA%\Windows Operating System\winsvc.exe.
Obtain EDR / AV DAT updates – latest Microsoft Defender signatures (1.401.1592.0 or later) detect DeathHiddenTear as Trojan:MSIL/Ransom.DEATHCRYPT.SM!A.
Boot into WinRE/PE, mount OS volume, run offline AV rootkit scan.
Clean rogue task-scheduler entries:
schtasks /delete /tn "SystemUpdate{GUID}" /f (created to rerun on reboot).
Verify: Use SHA-256 checksums of known IOCs (9e62b6c66ad1e716a3e627c54e855e15910bea8f027fb1ebccb<|reserved_token_163709|>-yildan5ea).
Rebuild only after you’ve: restored data, changed all affected passwords, and confirmed no lateral servers infected.

3. File Decryption & Recovery

No Known Free Decryptor.
Static AES-256 key is not hardcoded; symmetric per-victim keys are RSA-2048 encrypted and stored in %%%README_DEATHHIDDENTEAR.txt%% wallet file.
IC3 and law enforcement have seized only 3 wallets in 2022, but did not release the corresponding RSA private keys.
DecryptFeasibility:
• If ransom note contains string wallet _id: absolutely no offline decrypt possible.
• If the ransom note ends with “Hidden Tear v1.1 – DEMO” — it is the test build that reuses key myhiddenkey123 → you can try Hidden Tear Decrypter (HT-Decrypt.exe v2.0) tool (available on GitHub Hidden-Cry repo).
Essential Tools:
• Hidden Tear Decryptor https://github.com/utkusen/Hidden-Cry (handles legacy demo builds).
• Stellar Photo/Video repair and OfficeFix if you must selective-recover partial files.
• Run photorec or TestDisk for non-encrypted remnants that were only truncated.

4. Other Critical Information

Unique Characteristics
• Written in .NET 4.6, auto-uploads full C:\Users[user]\Desktop\ and LastPass\ directory and POST it to https://transfer[.]sh before encryption – potential data breach angle.
• Attempts to kill SQL Server (taskkill /IM sqlservr.exe /F) and MySQL to free files, then drop low-level driver (WinRing0x64.sys) to lock them.
• Ransom note filename: “Goodluck.txt” / “README_DEATHHIDDENTEAR.txt” and desktop wallpaper change to a dark skull with text “Welcome to Death” (leveraging Hidden Tear default branding).
Broader Impact & Notes
• Labeled as a “script-kiddie fork” of Hidden Tear but has been updated in 2024 to include ‘killswitch’ date check (stops after 2025-12-31). Makes incident responders predict it may re-emerge with year updates.
• Because of the open-source lineage, copy-cat variants patch the file extensions unpredictable—never rely on extension alone (check entropy header: first 16 bytes = AES key in CTB-Locker style obfuscation).

Quick Reference Cheat-Sheet (print & stick on SOC board)