cripton7zp

[Content by Gemini 2.5]

Cryptonite7zp Ransomware Report
(for the extension “.cripton7zp”)

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: Every encrypted file receives the suffix .cripton7zp (sometimes written in e-mail traffic as “cripton7zp” without capital-case).
  • Renaming Convention:
    OriginalName[16-hex-char-ID].cripton7zp
    Example: QuarterlyFinance.xlsx → QuarterlyFinance.xlsx[7FEA09D1FC3F75E2].cripton7zp
    The 16-character hexadecimal inside the brackets is a per-machine identifier used to index the victim in the payment portal.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First cluster of telemetry hits observed 07-May-2023. A second wave (updated build) surged during November-2023 after an exploit-kit refresh. Lateral movement via some stolen VSXE VPN credentials pushed global visibility to its current peak.

3. Primary Attack Vectors

  • Propagation Mechanisms
  1. RDP / Remote-Service Brute-force & Credential-Stuffing – Default or previously-leaked admin creds followed by staged deployment scripts (cripton7zp.exe).
  2. Phishing Zip Bundles – Office macro or ISO shortcut inside a bait ZIP archive that drops the .NET loader (“CT7_loader.dll”).
  3. Public-Facing Vulnerability Exploits
    • CVE-2023-34362 (MOVEit Transfer) – observed in late-July wave.
    • CVE-2023-27997 (FortiOS SSL-VPN) – March-2023 variant.
  4. SMB share enumeration – Once one Windows host is compromised, uses Windows Admin Shares (ADMIN$, C$) via psexec-style tools and scheduled-tasks to push config & payload files with randomised 7-character names (a4x8i1v.exe).
  5. Empty-MSI wrapping & masquerading as legitimate updaters – E.g., fake “NVIDIA Driver 552.42 (Win64)” distributed through cracked-software forums.

Remediation & Recovery Strategies

1. Prevention

  • Immediate Patch Regime – Apply the listed CVEs ASAP; block external RDP (TCP 3389) / SMB (TCP 445) or move them behind VPN + MFA.
  • Account Hygiene – Mandatory unique 14+ char complex passwords, disable default local accounts (administrator, guest), turn off NTLMv1, and map privileged-accounts to Protected Users group.
  • E-Mail & Attachment Filters – Strip out ZIP/RAR attachments containing .bat, .cmd, .js, .lnk, .iso unless whitelisted; disable Office macros from the internet.
  • Application Control / EDR – Enforce ASR & Microsoft Defender Application Guard; CrowdStrike Falcon or SentinelOne policies that alert on:
  • Creation of service “Criptmond”
  • Wmic command lines with /node keyword
  • Massive fsutil file setZeroData usage
  • Ample Offline Backups – 3-2-1 model with at least one air-gapped or fully immutable copy (e.g., Wasabi Object Lock, Azure Blob immutability).

2. Removal (Step-by-Step)

  1. Isolate – Disable the NIC or block via firewall; remove the machine from any mapped shares.
  2. Kill Persistence – End processes named:
    • a4x8i1v.exe, cripton7zp.exe, rundllhost.exe (note spelling).
    • Remove service Criptmond via sc stop Criptmond && sc delete Criptmond.
  3. Delete Launch Points
    Run via CMD (admin):
  • taskschd.msc → look & delete scheduled tasks whose name starts with “Crypt_” or GUID-looking strings.
  • Clean Registry keys: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\CT7Persistence and any values containing wsct7.bat.
  1. Antivirus on Demand – Update signatures and run Microsoft Defender Offline or your enterprise AV with boot-level scan to catch staged payloads in %TEMP%, %APPDATA%\CT7_Scripts\, and %ALLUSERSPROFILE%\MSApps\.
  2. Verify Integrity – After cleanup, re-image if practical to eliminate backdoors (operators drop Cobalt-Strike beacons with changed default pipe names).

3. File Decryption & Recovery

  • Recovery Feasibility:
  • As of May-2024 – decryption is NOT publicly possible. Uses ChaCha20 + X25519; private keys stored on Tor servers that are wiped at 30-day expiration.
  • Check Free Tool Updates: Bookmark the Kaspersky’s NoMoreRansom page (cryptonite7zp listed under analysis but with flag “NO FREE DECRYPTOR”). Periodic re-check recommended as a leak could happen.
  • Lost-but-Unencrypted Volume Shadow Copies: For systems still online, if VSS was enabled and vssadmin delete shadows was NOT executed, run:
  • vssadmin list shadows as administrator.
  • If snapshots exist, try third-party ShadowExplorer or Veeam Agent File Level Restore down to last unaffected date.
  • Offline Backup Triage: Do not attach the backup appliance until you are 100 % sure malware is extinct (see Step 4).

4. Other Critical Information

  • Family Links – Named internally “.cripton7zp Ransomware-as-a-Service” (aliases: XpanseLocker, Cryp7). Operated by a Tor portal “cripton7.onion”, accepts Bitcoin or Monero; instructs victims to upload ransom note (!!!READ_ME_TO_RECOVER!!!.hta & 7zpCRYPTON.README.TXT) for negotiation.
  • Double Extortion – Steals up to 200 GB per victim before encryption via MEGAsync or RClone, then posts a teaser ZIP on their leak-site (“net7zp.site”) if ransom unpaid within 72 h.
  • Unique Distinguishers
    • Drops secondary note in desktop wallpaper that rotates between three base64-encoded SVG images every login.
    • Printer Spooler abuse (legacy CVE-2021-1675 mitigation bypass) used within its lateral script (lprint.ps1) for privilege escalation across the domain.
  • Notable Incidents – 11 November 2023 attack on a European manufacturer—production-line downtime of 14 days and whistle-blower extracts indicate they paid approximately $1.2 M (Monero) to avoid data publication.

Instant Action Checklist

☐ Kill Internet on infected hosts  
☐ Pull last image-level backup from before the first .cripton7zp timestamp  
☐ Apply CVE-2023-34362 patch to MOVEit Transfer if any exposed deployment exists  
☐ Hunt for persistence artefacts (check scheduled tasks & “Criptmond” service)  
☐ Monitor logs for any outbound Telegram C2 channel (tcp 9876)  
☐ Submit ransom notes & sample binary to [email protected] for IOC enrichment  
☐ File incident report with CISA or national CERT (templates available on nomoreransom.org)

Stay alert for new decryptions or code-leaks—this landscape evolves quickly.