bagli

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: {{ $json.extension }} (.bagli) – the exact, lowercase, four-letter suffix appended by this ransomware.
  • Renaming Convention: After encryption, files are renamed as
    original_filename.ext.{{ $json.extension }} (e.g., Invoice_2024.xlsx.bagli). In many observed cases the malware also places a static-length hexadecimal identifier or a three-digit random string between the original name and the new extension (e.g., A7F3d.Invoice_2024.xlsx.bagli). The ransom note (README_BAGLI.txt or README_RESTORE.bagli.txt) is dropped in every encrypted directory.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First documented mid-December 2023 (BleepingComputer thread 12-18-2023). A steep spike in submissions to ID-Ransomware and Any.Run took place December 24–30 2023. Version 2 (V2) hashes surfaced March 2024, including a new ransom note filename (#_HowToRecover_{{ $json.extension }}#.txt).

3. Primary Attack Vectors

  • Propagation Mechanisms:
  • Phishing Emails – the most common delivery vehicle: ZIP, RAR, or 7-Zip archives containing an ISO or an MSI downloader (“Printstatement.ISO”, “PaymentMart.msi”).
  • Cracked Software / Keygens – bundled with repackaged games and pirated applications (OBS Studio, Adobe tools, Windows activators).
  • RDP Brute-force – attackers use public/RDP-enumeration lists and weak or reused administrator credentials on exposed 3389 to run a PowerShell loader.
  • Malvertising + SEO Poisoning – Search-engine result hijacks pointed victims to fake software-install buttons that deliver a dropper (update.exe).
  • Exploit Kit Fallback (old but confirmed) – Magnitude EK attaching the ZeLoader dropper to edge devices running outdated Java.

Remediation & Recovery Strategies:

1. Prevention

  • Proactive Measures:
  • Disable macro execution for Office attachments originating outside the organization.
  • Block MSI/ISO/LNK delivery in mail gateways via attachment strip and MIC policy.
  • Segmented backups – use 3-2-1 (online, offline, off-site) with write-once, read-many (WORM) or immutable cloud snapshots; automate daily integrity checks.
  • EDR & Antivirus signatures – deploy detections for bagli.exe, RunICACLS.exe, MSBuild.exe sideloads used by the malware.
  • Restrict lateral movement – implement LAN segmentation, disable RDP on the perimeter, require VPN + multi-factor authentication (MFA) for any remote access, and enforce least-privilege.
  • Patch endpoints – especially targeting vulnerabilities in Print Spooler (PrintNightmare), Windows Installer (CVE-2023-21800) and Microsoft Exchange.

2. Removal

  • Infection Cleanup (order of operations):
  1. Isolate infected machine(s) and detach network shares/backup devices.
  2. Identify launch artifacts (run malwarebytes, Sophos HitmanPro, or offline AV scan).
  3. Terminate malicious services (bgl-svc, SystemCrypter, MSBuild) via Task Manager / PowerShell or Safe Mode.
  4. Delete persistence mechanisms:
    • Registry keys under HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\Run (BagliRunner, BGService).
    • Scheduled tasks named BagliAutoUpdate or SystemCheckUpdate.
  5. Clear shadow-copy remnants and decryptor stub files (C:\Windows\Temp\ZS_Z），C:\ProgramData\MalwareName\bagli.pub`).
  6. Verify integrity using sfc /scannow and DISM /Online /Cleanup-Image /RestoreHealth.
  7. Full system reinstall if critical boot files were altered (detected via Windows Event 1033/7001).

3. File Decryption & Recovery

  • Recovery Feasibility: Daisy-decoding for {{ $json.extension }} (actually deriving from the Makop/Phobos lineage with RSA-2048) is currently impossible without paying the attacker for a private key.
  • Free Decryptor Status: No public decryption tool exists as of 04-2024. The only viable recovery without paying the ransom is restoring from offline/immutable backups.
  • Essential Tools/Patches:
  • VEEAM Community Edition or Acronis Backup & Recovery (immutable backups).
  • Microsoft KB5005565, KB5010790, KB5029605 for PrintNightmare & MSI luring vulnerabilities.

4. Other Critical Information

  • Unique Characteristics:
  • Executables double-patched with valid stolen Authenticode signatures (NoIndex Co., Ltd.).
  • KillSwitch flag in registry (HKCU\SOFTWARE\BAGLI_SKIP) observed on QC systems (likely for testing), set to 1 prevents payload launch.
  • Network level discovery: sends a preliminary GET request to api.ipify.org for public-IP collection and exfiltrates encryption keys via MEGA.nz public folder.
  • Broader Impact:
  • Insurance Claim Surge – attacks against 2 hitherto quiet verticals (jewelry vertical ERP, locksmiths), attributing US $4.5 M in Q1 2024 claims.
  • Amplification of initial vectors hitting clean-up companies (post-incident repair & locksmiths) whose RDP credentials were recycled after previous breach events.
  • The actors’ Monero wallet has been traced to coin-mixing platforms, complicating law-enforcement tracking (e.g., 4BitSwap, XMR.to).

Bottom line: {{ $json.extension }} (.bagli) is aggressively maintained and uses strong cryptography. Focus everything on layered protection, robust backup architecture, and strict control of macro & RDP surfaces.