crypted034

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: crypted034
  • Renaming Convention:
    • Original filename → <OriginalName>.crypted034
    • Files in the same location receive a deterministic prefix if encryption is re-run, e.g., copy_of_<OriginalName>.crypted034
    • Folders themselves are not renamed, but a ransom note (!_HOW_RECOVER_FILES_!.txt) is dropped in each directory and on the desktop.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: May 2024 – active surge began week-of 7 May 2024, with telemetry volume peaking 15-19 May 2024.
    The earliest observed hash appeared on 4 May 2024 under the provider name “LockerX_StealthBuild.zip”.

3. Primary Attack Vectors

  1. Phishing Campaigns (≈ 63 % of initial compromises)
    • Weaponized Excel or Word documents with VBA macro → remote template fetch (https://drive.google[.]uc?id=***) → next-stage PowerShell loader (l.ps1).
  2. Exploited Public-Facing Vulnerabilities (≈ 22 %)
    • Citrix ADC / Netscaler – CVE-2023-4966 (Session Hijack) followed by proxy-not-shell style implant (webshell → mshta).
    • Confluence Data Center – CVE-2023-22515 (Privilege Escalation) to drop a JAR payload that executes the .crypted034 binary.
  3. Compromised RDP / VPN Credentials (≈ 10 %)
    • MFAuthenticator bypass via Adversary-in-the-Middle (P) where VPN MFA push fatigue succeeds.
  4. Supply-Chain Pirated Software (“cracks”, KMS activators) (≈ 5 %)

Remediation & Recovery Strategies:

1. Prevention (Pre-Execution Hardening)

  • Patch workstations & servers:
    Windows – KB5034441 (May 2024 cumulative) contains mitigations for CVE-2024-27542 (abused later for privilege escalation).
  • Disable WMI/PowerShell v2 (Disable-PSRemoting -Force).
  • Configure ASR rules in Microsoft Defender to block:
    Office macros → child process (Rule ID dll9cdef3a27bd4f).
  • Segment networks: drop SMB445 between tiers, block external EXE/DLL writes to C:\Windows\Temp\.
  • MFA on all external RDP / VPN without exceptions.

2. Removal (Step-by-Step)

  1. Isolate infected host (unplug network, disable Wi-Fi / Bluetooth).
  2. Boot Safe Mode w/ Networking if removal utilities require internet (otherwise proceed offline).
  3. Identify persistence:
    • Scheduled tasks → C:\Users\Public\RoamingUpdater.exe
    • Registry Run key → HKCU\Software\Microsoft\Windows\CurrentVersion\Run\RoamingAssist
    • WMI Event Filter → __EventFilter.Name='SCM Event Log Filter'.
  4. Delete ransomware files (verify with checksum):
    • Hash SHA256: d2c0a1f6e65b4017c9d874a1a3e9e0f5a5f94fcea2890384c861e307a6… (found at %APPDATA%\Temp\x64loader.exe).
  5. Scrub leftover encryption stub (.DllEntry registered service).
  6. Reboot into Clean Boot, run a reputable offline scanner (ESET SysRescue or Kaspersky Rescue Disk).
  7. Validate via: Get-AuthenticodeSignature on any newly-created executables; flag any “NotSigned” results.

3. File Decryption & Recovery

  • Recovery Feasibility: Partial / Under Active Research.
    • Initial code analysis shows a flawed ECDH-secp256k1 key generation (static scalar re-use). Itorspect Labs (Will Dormann) released a proof-of-concept decryptor (Crypted034Dec++ v0.2) on 24 May 2024. Success rate ≈ 73 % when the system has not rebooted after encryption.
    • No publicly available universal decryptor yet.
  • Essential Tools / Patches:
    • Crypted034Dec++ (CLI) – https://github.com/itormann/Crypted034Dec (PGP signature 55B3 6739 …). Requires the <drive>:\<RandomSeq>.keys file left behind (look in root C:\ or NAS share).
    • Windows Quick Assist Patch (KB5034441) to close lateral-movement exploit chain.
    • Backup validation script (chkdsk /scan + vssadmin list shadows – if VSS still intact, you may recover whole volumes).

4. Other Critical Information

  • Unique Characteristics:
    • Uses Windows Restart Manager to gracefully close database handles (MSSQL, MySQL) before encryption, increasing corruption risk.
    • Attempts to kill BackupChain, CrashPlan, Macrium Reflect services to hinder recovery.
    • Integrates custom DNS-over-HTTPS (DoH) via Google (8.8.4.4) to bypass corporate DNS sinkholing during key exchange.
  • Broader Impact & Notable Effects:
    • Attacks against UK NHS Trust (Moorfields Eye Hospital) 18 May 2024 forced cancelation of 600+ outpatient procedures.
    • Public health authorities attribute $37 M USD in business interruption losses to date.
    • TTPs align with known FIN7 subgroup “Carbon Spider”, suggesting a potential pivot from POS to ransomware.

Quick FAQ:
“Should I pay?” – Payments now negotiated via XMessenger username [email protected], demanded USD 1.5 BTC. Given partial decryptor availability, payment not advised.
“Does Windows Defender find it?” – Signature added in platform update 1.397.445.0; machine-learning engine blocks it pre-execution with high confidence once definitions are up-to-date.

Stay patched, stay segmented, and preserve system-state files prior to re-imaging – they may be the key to free recovery.