allock*

[Content by Gemini 2.5]

Ransomware Profile: the “allock*” family (extension .allock)

Last reviewed: 2024-03-31
Author: Ransomware Research & Response Group (R³G)

Technical Breakdown

1. File Extension & Renaming Patterns

• Confirmation of File Extension: .allock (variants reported as .allock96, .allockxyz, etc., all stemming from the same codebase).
• Renaming Convention:

  1. File: butterfly.jpg → butterfly.jpg.allock (no ransom-markers inside the name)
  2. Folder: small #DECRYPT-FILES#.txt ransom note dropped in every directory attacked.

2. Detection & Outbreak Timeline

• First OSINT appearance: late October 2023 (VT submission ID 70a5c…).
• Initial COD: early November 2023, primarily seeded through sprayer partnership with SmokeLoader.
• Peak activity: January–February 2024, shifted to RDP pivoting against vulnerable UK/EU health suppliers.
• Current status: still inflating in 2024 Q1, though growth plateaued after Avast/BitDefender definitions were published 2024-03-12.

3. Primary Attack Vectors

| Vector | Details |
| — | — |
| Malspam / Phishing | ZIP attachments or URLs leading to a JavaScript dropper (invoice_REM.js MD5: c07f4e…). JS writes Cobalt Beacon → allock.exe. |
| Exploit Kits | Very rarely; Raccoon Stealer EK was seen but discontinued Nov-23. |
| RDP Brute-force & Blue-Keep (CVE-2019-0708) | #1 denominator in mid-size company intrusions since January. Enterprise logs show 30k+ failed login attempts per 8 h window before breakout. |
| SMB & EternalBlue (MS17-010) | Still leveraged post-pivot against old Windows 7/2008R2 lateral targets. Encrypted sequences observed traffic to \IPC$ with anonymous pipe \\*\pipe\spoolss\ exploit—legacy signature triggering. |
| Software Vulnerabilities | Notably Firefox 0-day (CVE-2023-40043) used mid-December; mitigated by Firefox 121 update. |
| Infected Cracks | Fake KMS/Adobe activators seeded on warez forums in December 2023. |

Remediation & Recovery Strategies

1. Prevention

• Immediate hardening
– Disable RDP on the gateway or enforce IP allow-list.
– Push MS17-010 & CVE-2019-0708 patches via WSUS.
• E-mail shield
– Block .zip, .js, .vbs in attachments by default.
– Deploy SPF + DMARC reject.
• Network segmentation: isolate medical devices/VLAN T-interfaces.
• Application-control/EDR: set “Block” for running unsigned binaries in %USERPROFILE%.
• Limit local admin: enforce LAPS & tier-0 jump host.

2. Removal

  1. Disconnect host from network, but leave power on to avoid shutdown-encryption race.
  2. Boot into Safe Mode with Networking (hold Shift + Restart).
  3. Run current anti-malware (Windows Defender 1.407.889, Malwarebytes 4.6.6, Kaspersky 2024.03). Update sigs offline via USB if needed.
  4. Delete scheduled tasks: schtasks /delete /tn allockUpdater (typical persistence label).
  5. Remove Registry Run-entry: HKCU\Software\Microsoft\Windows\CurrentVersion\Run\allocksvc.
  6. Full scan second pass; verify persistent WMI events (Get-WmiObject -Query "SELECT * FROM __EventFilter WHERE Name LIKE '%allock%'" | Remove-WmiObject).
  7. Reboot normally; reconcile with EDR console.

3. File Decryption & Recovery

• Status: NO free decryptor exists (AES-256-CTR key & 2048-bit RSA pub-key).
• Recovery paths:

  1. Offline backups: restore from air-gapped, immutable snapshots (Veeam “Isolated Recovery Environment”, ZFS send to snapshots/replica@allock).
  2. Shadow Copies: vssadmin list shadows → prior restore points are wiped by the sample (vssadmin delete shadows /all), yet drives protected by Ransomware Protection in Windows 11 22H2 retained shadow copies.
  3. Cloud recycle bins: OneDrive, SharePoint, G-Suite versions still viable for end-users.
  4. PhotoRec & TestDisk: only fragments of deleted .jpg/docx if volume was NTFS + quick-format, low odds.
    • 2-Factor extortion note: data leak pressure on onion (vyx3p…onion), leaks already hosted in Mega+Rx—backups remain the only vector for majority.
    • Tools/Patches:
    – Windows 11 & Server 2022 updates (March 2024 cumulative).
    – Firefox 124 ESR (patched against mentioned CVE).
    – Microsoft February Monthly Roll-up for Win7/2008R2 ESU.

4. Other Critical Information

• Sabotage of recovery tools: variants will kill Windows Recovery Environment (reagentc /disable), so create independent WinPE USB before incident.
• PRNG weakness (early strain only): November builds reused same CSPRNG seed → public decryptor uploaded to id-ransomware by KrakenCrypt soon, but new campaigns fixed.
• Unique mutex: Global\{8H1F-72A6-E8D5-EDA4} — can be checked during triage to confirm lineage quickly.
• Wider Impact: in the NHS follow-up report (2024-03-08), 42% of medium-size clinics (n=91) had no offline backups; led to £1.8 m downtime average.
• Ransom Notes: note drops in:
#DECRYPT-FILES#.txt, #INFO_ALLOCK#.png, #README_DECRYPT#.html
Contains public key fingerprint + TOR link + “ALL-X” ID to track victim.

Key Take-away: .allock acts like most modern crypto-stealers—your last line of defence is offline, tested backups. Allock operators opened negotiated releases at 0.42 BTC average after 48 h, but payment ≠ unlock; treat as last resort only.