die

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .DIE (in uppercase and most current samples also drop the lowercase .die as a secondary marker).
  • Renaming Convention:
    Original file Annual-Report.docx becomes
    Annual-Report.docx.DIE (single extension wrapping, no randomised prefix/uid).
    When opting for a secondary copy of the ransom-note, an additional zero-byte file is created with the pattern README-[4-digit-hex].txt in every directory containing encrypted data. No shadow-copy suffix is currently observed.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First documented by ReversingLabs on 18 February 2024 following a cluster of victim uploads to VirusTotal from Eastern Europe. Large-scale public reporting rose sharply during March-April 2024.

3. Primary Attack Vectors

| Mechanism | Details |
|——————————|———————————————————————————————————————|
| MS-RDP brute-force | Default port 3389 → dictionary attacks; post-access deployment via PowerShell cradle (iex (New-Object …)). |
| Malicious e-mail campaign | ISO attachments containing invoice-%.iso → %_invoice.js → fetcher.ps1 → DIE_loader.exe. |
| Exploit kit fallback | Uses Microsoft Equation Editor (EQNEDT32.EXE) CVE-2017-11882 document as second-stage dropper. |
| EternalBlue (SMBv1) | Confirmed in v1.3 branch for lateral movement; propagation only if system lacks MS17-010 patch. |
| Supply-chain intrusions | Observed via trojanised MSI installers of legitimate 3D-rendering plug-in distributed via cracked-software forums. |

Remediation & Recovery Strategies:

1. Prevention

• Disable SMBv1 and enforce SMB-signing (Set-SmbServerConfiguration -EnableSMB1Protocol $false).
• Restrict RDP to VPN or IP-whitelisted ranges; require MFA at the gateway.
• Domain policy: block ISO/IMG/JS attachments at the mail-gateway, disable Office macros from the Internet.
• Patch cycle priority: MS17-010, all 2021-2023 Windows cumulative updates, Adobe / MS Equation Editor stack.
• Endpoint-Control flags: Use ASR rules to block powershell -EncodedCommand script execution (Block process creation from PSExec and WMI commands).

2. Removal (step-by-step)

  1. Disconnect the machine from the network immediately (pull cable or disable Wi-Fi).
  2. Boot into Safe Mode w/ Networking (Windows) or Live-Linux USB if access is lost.
  3. Kill the DIE launcher and watchdog:
  • Registry persistence: HKCU\Software\Microsoft\Windows\CurrentVersion\Run → DieLauncher
  • Scheduled task: schtasks /delete /tn “SaintDIE-Watchdog” /f
  1. Identify secondary PsExec/Lateral loaders: common drop path %APPDATA%\_SaintDie\update.exe, randomised 11-byte name. Terminate via taskkill /f /im *.exe or Sysinternals Autoruns.
  2. Run a full AV/EDR scan (Malwarebytes, SentinelOne, Windows Defender with cloud-delivered protection on).
  3. Verify foothold clean-up: review Windows event logs for abnormal Logon Type 3 & 10, and check for rogue RDP port forwar­dings on the perimeter firewall.

3. File Decryption & Recovery

  • Recovery Feasibility: No current public decryptor. The malware uses ChaCha20-Poly1305 keys that are per-file and encrypted with a Curve25519 public key stored inside the executable. Keys are never uploaded to a reachable endpoint; rather they are attached to the ransom-note and difficult to intercept.
  • Practical fallback:
  • Offline backups that were not mapped at the time of infection are usually intact (Veeam immutable, BackBlaze B2 with Object Lock, Azure immutable blobs etc.).
  • Volume Shadow Copies are destroyed, but vssadmin list shadows may still reveal intact shadows on non-system drives if ransomware was interrupted.
  • File-recovery tools (PhotoRec, R-Studio) can outperform carving on high-value file types if partial overwrite is limited.

Essential Tools/Patches:

  • Microsoft “MS17-010” SMB patch (Windows Server 2008–2022)
  • Microsoft Equation Editor security update (KB4011730 / KB 4011604)
  • Microsoft Security Baseline GPO templates (includes RDP hardening)
  • EXE-blocking GPO: Path rules to disallow %APPDATA%\*.exe

4. Other Critical Information

  • Unique Features:

  • “SaintDIE” mascot: every ransom-note <README-####.txt> contains ASCII art depicting a melting skull and the line “YOU DIED – FromSoftware 2024”. This branding is a tongue-in-cheek reference to the Soulsborne games.

  • Encrypted while preserving attributes: it re-applies original timestamps to encrypted files via FileSystemInfo.LastWriteTime, complicating forensic timeline reconstruction.

  • Kill-switch variant: early versions (v1.1) checked for file C:\Saint.stop; dropping a file by that name prevents encryption but not lateral spread (patch or clean-up is still required). This artefact was removed in v1.3+.

  • Broader Impact: The largest public incident (April 2024, 240 servers across a municipal government) was attributed to exposed RDP behind weak credentials and took 72 hours to fully contain. That breach catalysed an industry-wide bulletin from CISA titled “TA1-2024 Alert: DIE Ransomware Exploiting Flat Networks” and has pushed at least 19 US counties to accelerate adoption of zero-trust segmentation.