desolated

[Content by Gemini 2.5]

Technical Breakdown: DESOLATED Ransomware

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .desolated
  • Renaming Convention:
    • Standard pattern: <original_name>.<original_extension>.<email>.desolated
    • Example: [email protected]
    • Email address varies (latest samples use [email protected], older ones used [email protected], [email protected], [email protected]).
    • Directory trees are left intact; files at every depth are altered, giving victims an immediate visual cue of the breadth of compromise.

2. Detection & Outbreak Timeline

  • Approximate First Public Sighting: March 17 2024
  • Significant Spike: Early April 2024 (hundreds of submissions to ID-Ransomware and VirusTotal); second wave June–July 2024 (new variant using alternate note filename: DESOLATED_README.txt → How_To_Recover_Files.txt).
  • Detection Hash Reference: Signature now tracked by Microsoft, SentinelOne, TrendMicro, and several open feeds as “Ransom:MSIL/Desolated.A”.

3. Primary Attack Vectors

  • Propagate Vector 1 – RDP Brute-Force / Compromise:
    – Attacking default or weak Administrator passwords, then pivoting via BloodHound-style enumeration.
    – Common Port Scan Range: TCP/3389 (RDP) and TCP/22 with SSH credential-spray; once inside, lateral movement utilises net user, net localgroup administrators, and wmic process call create.
  • Propagate Vector 2 – Malicious Attachments in Emails:
    – ISO, IMG, and password-protected ZIP archives containing a .NET launcher (Desolated-KeyGen.exe, invoice_12736.appref-ms) that drops a small PowerShell stager.
    – Lures typically pretend to be “price quotation”, “wire transfer confirmation”, or “bank investigation letter”.
  • Propagate Vector 3 – Software Exploits:
    – Currently the most reliable observed infection path: exploitation of CVE-2019-19781 (Citrix NetScaler ADC/Gateway) and CVE-2021-34527 (Windows Print Spooler, aka “PrintNightmare”). The desolated loader stage injects into the Spooler service (spoolsv.exe) to evade EDR hooks.
  • Common AppLayer Target Vector:
    – Exploits exposed secure web access gateways (SonicWall, FortiGate) for VPN access, deploys RELOADED script and then DESOLATED payload.

Remediation & Recovery Strategies

1. Prevention

  1. Disable Legacy Protocols:
    • Turn off SMBv1 across the domain via GPO:
    sc.exe config lanmanworkstation depend= bowser/mrxsmb20/nsi
    • Disable RDP entirely if not required, or restrict it to VPN-only plus multi-factor authentication (MFA).
  2. Patch Immediately:
    • Apply May 2024 cumulative Windows update or superseding rollups (KB5034441 & KB5034857) – closes PrintNightmare vectors.
    • Update Citrix ADC/FortiGate firmware to latest recommended branch.
  3. Implement Application Control:
    • Enable Windows Defender ASR rules “Block executable files from running unless they meet a prevalence, age, or trusted list criteria”.
    • Deploy AppLocker or Microsoft AppControl to block unsigned .NET executables in %TEMP%, %APPDATA%, or user-writable locations.
  4. Backups:
    • 3-2-1 rule: 3 copies, 2 different media types, 1 offline/air-gapped.
    • Backup path must be write-protected via S3 Object Lock, ZFS readonly snapshots, or WORM tape. Validate restore monthly.

2. Removal (on an infected host)

  1. Isolate:
    • Disconnect from network (both wired & Wi-Fi).
    • Power-off uncontrolled remote services (Virtual Machines).
  2. Boot into Safe Mode (Windows) or LiveCD (Linux):
    • Windows 10/11: Hold Shift while choosing Restart → Troubleshoot → Advanced → Startup Settings → Safe Mode with Networking.
  3. Scan with Offline / Cloud-Init AV:
    • Use Windows Defender Offline or any vendor “Rescue Disk” (Bitdefender, Kaspersky, Sophos) to remove remaining traces (%SYSTEM32%\svchosts.exe, %TEMP%\logsa.dll, scheduled task UpdateGoogleChrome).
  4. Check & Prune Persistence:
    • Scheduled Tasks: schtasks /query /fo csv | find "Desolate"
    • Registry RunOnce & RunKeys:
    HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\UpdateSystem (value points at C:\ProgramData\WindowsUpdater.exe)
    • Service hidden with blank display name: sc.exe qc "" (clean via sc.exe delete).
  5. Post-Removal EDR Sweep:
    • Run full EDR scan with telemetry submitted offline, then enable network containment back with monitor-only for 24 h.

3. File Decryption & Recovery

  • Recovery Feasibility: At time of writing no free decryptor exists. DESOLATED deploys a 128-bit ChaCha20 stream cipher keyed with an imported RSA-2048 wrapped key; private key is stored server-side and never exposed.
  • Available Tools:
    • Use Emsisoft’s “Stop Djvu Decryptor” as a test file checker – it cannot decrypt DESOLATED but will confirm if the variant is in fact STOP (false alarm).
    • If backup strategy fails: contact reputed ransomware recovery firms for possible negotiated release (significant legal / risk caveats remain).
  • Patch Notes:
    – The ransomware kills EDR and deletes Volume Shadow Copies (vssadmin delete shadows /all /quiet), so recommend enabling immutable cloud backups instead of relying on VSS.

4. Other Critical Information

  • Unique Characteristics:
    • Creates “before & after” desktop wallpapers (C:\Windows\Temp\Desolated.jpg) that appear after first 15 encrypted files.
    • Extended sleep loop (exact 15-minutes) to crash some EDR sandboxes under short time-out configurations.
    • Leaves an alternating ASCII ransom-note filename (DESOLATED_INFO.txt, info_desolated.txt, How_To_Recover_Files.txt) in every folder – may confuse IR scripts that assume a single filename.
    • Known Ransom Amount: 0.02–0.08 BTC (~$1 200–$5 000) but discounts offered within 72 h; wallet reused across campaigns address-rotation pattern shows seldom rotated, aiding tracking.
  • Broader Impact / Sector Notes:
    • June 2024 campaigns hit three U.S. health clinics and one dental lab – proof that the group now includes HIPAA-covered entities in its targeting.
    • Brazilian and Turkish MSPs observed simultaneous infections, indicating the attackers are leveraging shared RDP/VPS providers; IOC overlaps using WHOIS registrations point to initial access broker (IAB) “RockSpider”.

Quick Reference Quick-Sheet (print & audit)

  1. Blocked Ports: TCP/3389 (RDP), TCP/22 externally unless VPN-over-mfa.
  2. Urgent Patches: KB5034441, Citrix ADC 14.1-49.23, FortiGate 7.4.3.
  3. Possible Desolated IOCs:
  • SHA256 hashes:
    • 84562f9ed4a91c68a193b78c0d56b441c5177203e49ecf8f553b197a4c111cb0 (primary payload, .NET 4.8)
    • 50b3a13cd948b5fbd5cf85d9c0f1e3312bf79f0ad4a0f8b9d5ce58f001e3c657 (task-scheduled updater)
  • Registry Keys: HKCU\Software\Agile\Desolated (stores victim ID & public key)
  • Process tree: svchosts.exe (note plural – not legitimate).
  1. Recovery scripts (open-source):
    – ShadowCopyTakeBack.ps1 – restores shadows when stager forgot to delete remote-snapshots on network-attached share.

Stay vigilant, patch quickly, and keep your incident-response runbook and backups battle-tested—DESOLATED tries hard to delete every recovery avenue you did not expect.