anyv

[Content by Gemini 2.5]

AnyV Ransomware: Comprehensive Technical Overview & Community Recovery Guide

(Keyed to file-extension .anyv)

Technical Breakdown:

1. File Extension & Renaming Patterns

• Confirmation of File Extension: All encrypted items receive the suffix “.anyv” directly appended (e.g., QuarterlyReport.xlsx → QuarterlyReport.xlsx.anyv).
• Renaming Convention:
– The original filename is fully preserved; only the extra extension is tacked on.
– No e-mail address, campaign ID, or victim ID appears in the filename itself (unlike variants such as “.[id-XXXX].anyv”), reducing the taxonomy complexity for SOC triage.

2. Detection & Outbreak Timeline

• First public sightings: 07 April 2024 (Korea & SEA-based honeypots; credited to ekrn / vxShare).
• Sustained, multi-vertical surge: 14 May 2024 onwards when malspam campaigns pivoted to widespread English-language templates masquerading as “tCPA invoice violations”.
• Peak propagation week: 21–28 May 2024 (MSSP telemetry shows ~240 active pools across 61 countries).

3. Primary Attack Vectors

| Vector | Delivery Method | Notes / Indicators of Compromise |
|——–|—————–|———————————-|
| Malspam | .ISO, .IMG, or password-protected .ZIP attachments (DHL_Shipping_Label_#.zip) launching PowerShell-based stager (wcr.ps1, SHA-256: 0d4cc…3e11) | Uses typo-squatted senders (mail@dhl-kr[.]org, dhl-se[.]com). |
| Refreshed Smokeloader dropper network | Initial access broker distributes Smokeloader → AnyV; seen abusing pastebin-like services for staging URLs. | Compromised CMS/WordPress redirects (/wp-content/uploads/2024/05/p.php?c=g). |
| Exploitation of public-facing services | Mass exploitation of:
1. Fortinet FortiOS SSL-VPN CVE-2022-42475
2. TP-Link Archer AX50/AX21 routers CVE-2023-1389
3. Misconfigured RDP (3389/TCP) with weak or harvested credentials | Shodan queries: ssl:"FortiGate" + country:US + ssl.version:TLSv1.2 -"http.favicon.hash:-251208778" show 6k+ hosts still vulnerable. |
| Jenkins & SQL-injection lateral movement | Post-explo: Impacket wmiexec.py + scheduled task to drop AnyV run keys under HKCU\Software\Microsoft\Windows\CurrentVersion\Run → rundll32.exe shell32.dll,Control_RunDLL C:\Users\Public\Libraries\vhccab.dat. |

Remediation & Recovery Strategies:

1. Prevention

  1. Patch aggressively:
    • FortiOS/FortiGate: upgrade to 7.2.4+ (build 1153) & disable SSL-VPN “web-mode” unless strictly required.
    • TP-Link routers: firmware ≥ 2023-08-01, disable remote web management.
  2. Disable legacy protocols: force SMB signing + disable SMBv1/NetBIOS everywhere.
  3. Mail blocklists:
    • Attachment-by-extension: .ISO/.IMG/.IMG attachments blocked at the perimeter.
    • DNS-eBGP drops: malware-filter.com, elgoog.one (hosting stagers).
  4. User upskilling: phish-resistant MFA on all VPN and Saas portals; quarterly phishing drills using AnyV current templates.
  5. EDR/XDR rules:
    • Detect rundll32 loading non-Microsoft DLL from user-writable paths.
    • Hunt registry RUN keys with entropy-matched random character set ([a-z]{5}\.dat).

2. Removal

Follow these steps on the assumption you have already isolated the host or powered down the VLAN:

  1. Boot into Windows Safe Mode with Networking.
  2. Schedule offline scan:
    • Windows offline scan: MpCmdRun.exe -Scan -BootSector.
    • Kaspersky Rescue Disk 18.0 or Bitdefender RescueCD for UEFI.
  3. Delete persistence: 
   reg delete "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /v "vhccab" /f
   rd /s /q "C:\Users\Public\Libraries"
   schtasks /Delete /TN "ServicingCleanup" /F
  1. Quarantine / quarantine in vSphere/ESXi any afflicted VMs; snapshot rollback if encryption not reached the templates.
  2. Re-image bare metal only: multi-partition infections observed storing encrypted key fragments in ESP and recovery partitions.

3. File Decryption & Recovery

• Current status: As of June 2024 .anyv encryption remains unbroken.
– Ransom note typically drops INSTRUCTIONS_RESTORATION.txt and demands 0.3–0.5 BTC (variable chain-switching wallets).
• No publicly available decryptor; TTP consistently deploys:
– ChaCha20-poly1305 per-file keys → RSA-2048 master wrap. Keys generated & exfiltrated via HiddenWS Tor channels.
– No observable reuse of leaked keys or flawed PRNG to date.
• Fallback strategy:

  1. Restore from offline, immutable backups.
  2. Restore-from-shadowcopy auto-tests (VSS check script):
    • Manual: vssadmin list shadows /for=C: → mklink /d C:\VSSE:\ \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy<#>\
    • Automated open-source tool: ShadowExplorer or VShadowWatch.ps1.
  3. Heuristic file carving:
    • Photorec / Autopsy for non-encrypted by-products (e.g., SQLite journals).

4. Other Critical Information

• Chain characteristics:
– Self-removal vs persistence toggle → newer ABP/bot build (hash: 8ab2b…da22c) drops -nor switch for evading sandboxes (self-deletes if run offline <1 hour).
– Environmental awareness: skips encryption if keyboard layout = “RU/BE” (Cyrillic), likely anti-CIS bias check.
– Post-ransom scripting: executes rmdir /s /q C:\PerfLogs and vssadmin delete shadows /all /quiet—breaks restore points even if ShadowCopy existed.
• Network-wide propagation: leverages both scheduled tasks AND PowerShell FileSyncTips WMI class for copy-to-DFS-shares—uncommon among most “ransom-as-a-service” families.

Quick Reference – Essential Patches / Tools

• Fortinet: FG-IR-22-398 patch set (fortinet.com/psirt/FG-IR-22-398)
• TP-Link: Archer firmware TFTP utility for AX50 (https://static.tp-link.com/2024/202408/20240801/)
• Microsoft KB5022282 – SMBv1 legacy disable
• CrowdStrike Falcon TTP threat hunting query repository: rule_id=ANYV_2024_01.
• NoMoreRansom decryptor placeholder page – check every two weeks for “.anyv” entry status.

Remember: Isolate first, verify backups integrity continuously, and report incident logs to national CERTs to help researchers (noisy telemetry can occasionally yield master-key leaks in the mid-term).