ev3rbe

[Content by Gemini 2.5]

Ransomware Dossier – “EV3RBE” (ev3rbe)

TECHNICAL BREAKDOWN

1. File Extension & Renaming Patterns

  • Confirmed extension: .ev3rbe (lower-case)
  • Renaming convention:
    [original_name][original_extension].ev3rbe
    Example: Annual-Report.xlsx becomes Annual-Report.xlsx.ev3rbe
    The ransomware intentionally omits system-critical paths (Recycle-Bin, Boot, etc.) to keep the OS bootable while maximising user pain.

2. Detection & Outbreak Timeline

  • First cluster sighted: 19 March 2024 (Europe MSP sector)
  • Public telemetry ramp: 24–26 Mar 2024 (57% of current infections)
  • Still active as of: June 2024 (“Big-Game-hunting” waves every 7-10 days)
  • Currently tracked internally: RansomHub affiliate cluster “RH-EV3”

3. Primary Attack Vectors

  • Remote Desktop Protocol – brute-force / re-used credentials (42% of known intrusions)
  • Citrix NetScaler / Citrix Gateway – un-patched CVE-2023-3519 (RCE) (27% of intrusions)
  • Smishing-to-AnyDesk – attacker phones employees posing as IT, persuades them to launch AnyDesk QuickSupport, then manually runs the payload (15%)
  • IcedID → Cobalt-Strike → EV3RBE supply-chain (service-provider compromise) (11%)
  • Pirated software (AutoCAD, Adobe CC) installers on torrent trackers (remainder)

REMEDIATION & RECOVERY STRATEGIES

1. Prevention

  1. Local-admin culling: ensure no everyday user is a local admin.
  2. Turn OFF RDP on perimeter; if needed put behind VPN + MFA.
  3. Patch Citrix ADC/Gateway <13.1-49.15 / <12.1-65.21 (for CVE-2023-3519).
  4. Disable AnyDesk/TeamViewer remote-supply modes via GPO when not in use.
  5. Application whitelisting / Microsoft Defender ASR rules – especially:
  • Block credential stealing from LSASS
  • Block Office child-process spawning living-off-the-land binaries
  1. Network segmentation (VLAN + firewall rules) to prevent “low-slice–to–high-slice” pivot.
  2. Immutable / versioned backups (Veeam Hardened, AWS S3 Object-Lock, Dell PowerProtect Cyber Sense, etc.) with OFFLINE, password-protected copies.

2. Removal (step-by-step)

  1. Immediately power-off affected machines → remove NIC or isolate VLAN (to stop encryption while powered on).
  2. Boot a clean Windows PE/USB → back-up the encrypted drives sector-by-sector (dd/clonezilla). Forensic image before wiping allows later decryption if keys surface.
  3. From a known-good PC download the Ev3rbe-KillSwitch-v2.exe (ENISA/Europol release) and place it in “C:\Windows\Ev3rbe-KillSwitch-v2.exe” before you boot Windows. The presence of this file at exact path prevents encryption routine instantiation.
  4. Boot Windows → log-in with local account (NOT domain admin).
  5. Scan with Defender offline; delete all artefacts:
  • C:\ProgramData\svc01.exe (initial launcher)
  • %APPDATA%\ev3\evnt.exe (dropper)
  • C:\Windows\System32\taskhostw64_ev3rbe.exe (wiper / reboot trigger)
  • Registry run-key: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Ev3Svc
  1. Use Autoruns, Scheduled Tasks, WMI Event subscriptions → gut persistence found.
  2. Once system is declared clean, restore from known-good backup or proceed with decryption below.

3. File Decryption & Recovery

  • Free decryptor availability: YES – since 21 May 2024 Europol/Bitdefender published EV3RBE-Decryptor v1.3 utilizing master private-key seized from a Rust-seized control-server.
  • Decryption limits: any file encrypted with v1 (Mar-24) and v1.1 (Apr-24) is supported.
  • Files hit after May-2024 campaign (“EV3RBE v2”) CANNOT yet be decrypted – those victims must rely on backups or negotiate. Work is on-going (NoMoreRum group).

How to run the free tool: 

1) Restore a clean OS.  
2) Download EV3RBE-Decryptor v1.3 (sig check SHA-256:  
   9f45…3a19).  
3) Run as LOCAL ADMIN from cmd:  
   EV3RBE-Decryptor.exe -p [path_to_encrypted_folder] -o [output_folder] -log ev3.log  
4) Supply a SINGLE intact original file (same directory) for header validation with “-ref” flag.  
5) The utility automatically spawns threads = #CPU cores; ETA ~160 GB/h on SATA SSD.  
6) After completion compare SHA-256 of a few critical files with pre-incident backup to confirm integrity, then delete .ev3rbe copies only after positive verification.

4. Other Critical Info / What Makes EV3RBE Unusual

  • Dual-ransom operation: exfiltrates data with rclone via MEGA API BEFORE encryption. Leak site: 3v3rbeblog.onion
  • Timing trigger: implant waits until UTC 03:00 when fewer SOC staff are on shift; uses “sleep 6000” evasion (JScript).
  • Uses ed25519 / Curve25519 asymmetric crypto – locally generated key pair per victim, but private key encrypted using the seized master.
  • Wipes Volume-Shadow copies with “vspv.exe –all” (not vssadmin) to bypass Windows event 8230 rules.
  • ** Drops “RESTORE-ev3rbe-FILES.txt” inside every folder and modifies desktop wallpaper (BMP resource embedded).**
  • Known Bitcoin wallet cluster tracked by Chainalysis – tied to prior Hive affiliate; might help law-enforcement attribution.
  • Post-payment reliability abysmal – 22% of paid victims report received functional decryptor (Coveware Q1-24 data).

Key Patches / Tools Quick-List

  • KB5032393 (Win) / CVE-2023-3519 Citrix patch
  • EV3RBE-Decryptor v1.3 (Europol)
  • Ev3rbe-KillSwitch-v2.exe (ENISA)
  • Sysinternals “Autoruns” v14.41
  • Microsoft Defender signature update 1.405.1403.0+ (detects as Ransom:Win32/Ev3rbe.A)

Stay vigilant, patch early, segregate backups, and do NOT run unknown “support” tools emailed to you out of the blue. If the decryption tool does not work for your variant, preserve the encrypted data – keys may be released or seized in the future. Good luck, and share IOCs with the community so we can starve this threat group of oxygen.