fmopq

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: FMOPQ
  • Renaming Convention:
  • Victim files are renamed in the following pattern: <OriginalName>.<OriginalExt>.fmopq (e.g., Project.xlsx → Project.xlsx.fmopq).
  • No hexadecimal or email-based prefix/suffix is inserted, making FMOPQ easy to recognize in directory listings.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First submissions to public malware repositories and ID-Ransomware were observed in late-August 2021; large-volume campaigns peaked during September–October 2021 and continue sporadically.

3. Primary Attack Vectors

  • Propagation Mechanisms:
  • Phishing e-mails containing password-protected ZIP or ISO attachments that launch a malicious .docm or .xlsm document.
  • Exploitation of unpatched Microsoft Exchange servers (ProxyShell CVE-2021-34473 / CVE-2021-34523 / CVE-2021-31207) to drop the payload via PowerShell.
  • Compromated RDP / VPN credentials harvested by info-stealers and sold on underground forums.
  • Secondary movement inside LAN via SMB/PSExec and the ubiquitous “EternalBlue” (MS17-010) when victims have still not patched.

Remediation & Recovery Strategies:

1. Prevention

  • Proactive Measures:
  • Patch early, patch often: Windows, Exchange, VPN appliances, and firmware.
  • Disable SMBv1 at the organisational level; enforce NLA on RDP; use 2FA for any remote-access service.
  • Mail-gateway rules: strip ISO/VBA macros at the gateway; sandbox incoming attachments.
  • Application whitelisting / Windows Defender Application Control to block unsigned payloads.
  • Centralised logging + EDR: ensure Tamper Protection is on for Windows Defender / third-party AV.
  • Maintain at least one off-line, off-site backup with an immutable retention period (e.g., S3 Object Lock).

2. Removal

  1. Isolate: Power down the infected host’s switch port or disable Wi-Fi; disable scheduled tasks and services (search for random 6-10 character names).
  2. Boot to Safe Mode with Networking or use a WinPE/USB recovery disk.
  3. Delete malicious artefacts:
  • %LOCALAPPDATA%\[random]\[random].exe (or .dll) – main encryptor.
  • Run keys under HKCU\Software\Microsoft\Windows\CurrentVersion\Run referencing the same random binary.
  • Scheduled task \Microsoft\Windows\[random name] that re-launches the binary.
  1. Run a reputable AV/EDR scan (Defender, ESET, Kaspersky, Sophos, etc.) to quarantine residual components.
  2. Patch the intrusion vector (Exchange, VPN, RDP password) before returning the host to production.

3. File Decryption & Recovery

  • Recovery Feasibility: FMOPQ belongs to the STOP/Djvu v251 family; it uses an online key fetched from the criminal C2 except in the rare cases when the victim’s machine is offline.
  • If your variant shows extension .fmopq, check the personal ID within the ransom note (_openme.txt):
    • IDs ending in t1 are offline keys – decryptable with the free Emsisoft STOPDecrypter (download from emisoft.com/ransomware-decryption-tools).
    • Any other ID indicates a server-side key – no free decryptor exists; your only options are clean backups or third-party negotiation (not recommended).
  • Essential Tools/Patches:
  • Emsisoft STOP decryption tool (kept updated for all offline variants).
  • MS17-010 (EternalBlue) patch, Exchange Cumulative Updates (CU) ≥ Aug 2021, ProxyShell mitigation script (MSERT).

4. Other Critical Information

  • Additional Precautions:
  • FMOPQ bundles Azorult info-stealer; assume passwords, cookies and cryptocurrency wallets are compromised and rotate them after cleanup.
  • It deletes Volume Shadow Copies (vssadmin delete shadows /all) and disables Windows 10 ransomware protection—both must be re-enabled post-removal.
  • Broader Impact:
  • STOP/Djvu variants like FMOPQ account for >70% of ransomware submissions to public engines because they target home users and small businesses through cracked-software sites as well as e-mail.
  • The criminal group’s volume-based model (low ransom, ~USD 480–980) keeps payment pressure high; paying is doubly risky because it funds additional stealer campaigns.

Bottom line: Patch internet-facing services, harden the mail gateway, keep offline backups, and test them—then even FMOPQ’s “friendly” ransom note becomes nothing more than an annoyance instead of a disaster.