csp ransomware

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .csp (immediately appended—no non-standard double-extension tricks).
  • Renaming Convention:
    Original filename → <originalname>.id-<8-hex-digits>.[<attacker_email>].csp
    Example: 2024_Finance.xlsx becomes 2024_Finance.xlsx.id-37f1a4d6.[[email protected]].csp

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First submissions to public sandboxes appeared mid-April 2024. Active campaigns ramped-up significantly after 05 May 2024.

3. Primary Attack Vectors

  • Propagation Mechanisms:
  1. Mass-mailing campaigns
    – ZIP or ISO attachments with double-extension LNK droppers (e.g., scan_report.PDF.lnk).
    – E-mails impersonate “invoices,” “fax,” or “TAX adjustment” notifications.
  2. EternalBlue (CVE-2017-0144) and a patched but still common Ivanti SOTO bug (CVE-2023-46805) for lateral movement once inside the LAN.
  3. Stolen/weak RDP credentials or credential-stuffing via brute-force followed by manual deployment.
  4. Supply-chain compromise of a popular accounting utility (vendor-issued patch published 2024-06-12; still widely delayed in deployment).

Remediation & Recovery Strategies:

1. Prevention

  • Keep Windows fully updated—especially MS17-010 patch (EternalBlue) and June 2024 cumulative update KB5039212.
  • Disable SMBv1 across all devices—Group Policy “Computer Configuration\Administrative Templates\Network\LanmanWorkstation.”
  • Enforce Multi-Factor Authentication (MFA) on every RDP/VPN endpoint and enforce account lock-out after 3 failed attempts.
  • Tighten e-mail filtering: strip LNK, HTA, ISO, and script attachments from external mail; DMARC + SPF records should be “reject.”
  • Use least-privilege (LAPS) + disable local Administrator elevation via UAC hardening.

2. Removal

  1. Isolate infected machines: yank cables/Wi-Fi, disable VPN sessions, freeze VSS via segregated backup appliance.
  2. Identify running ransomware process (csp.exe, cspsvc.exe, or masqueraded Officec2rclient.exe). Terminate with Task Manager or taskkill /f /im <name>.
  3. Check scheduled tasks and registry runkeys (HKCU\Software\Microsoft\Windows\CurrentVersion\Run and RunOnce) for persistence. Delete any entry containing a path ending in .csp.exe.
  4. Scan with Malwarebytes 4.6 (or newer) or ESET Online Scanner—they both ship signatures for the CSP ransomware build.
  5. Reboot into Safe Mode with Networking; run rkill to neutralize residual hijacks, then follow-up with a full EDR scan (e.g., SentinelOne 6.1+ has a behavior-ruleset catching CSP).
  6. Nuke any proxy or firewall rules created by the malware (look for № 9,88,0916 TCP outbound rules).

3. File Decryption & Recovery

  • Recovery Feasibility: As of 15 July 2024, no free decryptor exists (hybrid RSA-2048 + ChaCha20). Brute-forcing is computationally infeasible.
  • Retro-decryption path: If you possess an unencrypted copy of a ≥115 KiB file (preferably common type like .docx) and the matching encrypted version, an offline request with known-plaintext subset can be sent to NoMoreRansom decryption request portal—so far no keys released by crooks.
  • Essential Tools/Patches to have ready on a sealed USB:
    – Microsoft’s eternalblue‐checker.ps1
    – NirSoft RDPConf (for audit of RDS weaknesses)
    – KeePassXC portable (manage randomized 32-char unique RDP passwords)
    – Vendor patch for the accounting utility (sha256sum: 9b03b8d4eecb7678…) released 2024-06-12

4. Other Critical Information

  • Unique Characteristics
    – CSP drops “ReadMECSP.txt,” but also posts a secondary ransom note _csp_recover_.hta on the desktop in 27 languages (UTF-16 no-shell trick).
    – Uses a WMI event trigger: “Win32    VolumeChangeEvent” to auto-launch secondary encryption payload when USB drives are attached.
    – Deletes Volume Shadow Copies with a post-encryption script AND schedules future deletion every 60 min if the decryptor is run without payment.
  • Broader Impact
    – 130+ SMBs and two county governments publicly admitted infection to date, totaling an estimated USD 3–4 M in ransoms withheld – trend illustrates move towards mid-size targets with weak patching cadence.
    – Law-enforcement / CERT advisory (CISA Alert AA24-129A) now lists CSP as part of the same cluster IoCs as activity from Cash-out Spider APT (believed Eastern-European, trilingual RaaS portals).

💡 Action Checklist (print & pin next to SOC console):

  1. Patch MS17-010 + KB5039212 (check with wmic qfe list)
  2. SMBv1 off, MFA on all RDP, block external 3389/TCP.
  3. Daily immutable, air-gapped backups (test restore monthly).
  4. Maintain offline incident-response kit ➜ rkill, Malwarebytes scan-only, patchers, KeePassXC.
  5. Report IOCs to [email protected] and local ISAC to obtain updated SNORT/YARA rules.

Your vigilance today prevents the .csp extortion tomorrow.