bgcib

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Ransomware BGCIB Technical & Recovery Guide

Last revised: 02 June 2024

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .bgcib
    BGCIB uses the eight-character lowercase extension .bgcib appended after the original file extension (e.g., Annual_Report.xlsx.bgcib). There is no preceding dash, bracket or timestamp.
  • Renaming Convention:
    filename.ext ➜ filename.ext.bgcib

Common victims report folder names that begin with four random capital-letter combinations followed by a short 7–9 digit number; the ransom note is then placed as FILES_NOTE.TXT in every impacted directory.

2. Detection & Outbreak Timeline

  • Approximate Start Date / Period:
    Distributed-trace records from multiple CERTs place the first surge of BGCIB e-mail hash-matches on 4 April 2024, after which infection telemetry climbed rapidly over the following three weeks.

3. Primary Attack Vectors

  1. Spear-phishing via ISO & CAB archives
    Office or ZIP attachments contain an embedded ISO/Cabinet file (Invoice-9999-2024.iso / Annual-Statement.cab) which, once mounted, launches a disguised MSI or LNK → LH_SERVER.exe → BGCIB loader.
  2. Compromised RDP (stolen or brute-forced)
    Common ports 3389/5934; attackers then run ipscan.bat → anydesk.exe → tool-dropper svcbhtrsvc.exe.
  3. Exploitation of CVE-2024-21413 (Outlook RCE)
    Weaponised calendar invites or RTF e-mail body triggers archive download (bgcib_loader.dmp.rar) and MSI sideload.
  4. Cracked software & adware bundles (Pirated Adobe CC, MS Office KMS injectors)
    Secondary wave observed in Latin-American piracy forums, smuggling installer.exe that drops BGCIB + RedLine infostealer.

Remediation & Recovery Strategies

1. Prevention

| Control Layer | Specific Action |
| — | — |
| E-mail & Attachment Filtering | Block .iso, .cab, .vhd, .msi, or archives containing these by default. Tag external mails with [EXTERNAL] and quarantine HTML-embedded invites. |
| Patch & Hardening | 1) MS Update 2024-03B (Outlook RCE fix)
2) Enable Credential Guard & disable NTLMv1.
3) Disable or limit RDP exposure; mandate MFA on any remote gateway (prefer RDP Gateway with 2FA). |
| Network Segmentation | Implement Zero-Trust; restrict SMB 445 & WMI across VLANs. |
| Least-Privilege Software | Enforce AppLocker / Windows Defender ASR rules blocking child-process creation from mounted drives (C:\Windows\System32\msiexec.exe only allowed from approved path). |
| Backup Hygiene | 3-2-1 methodology with irrevocable off-site snapshots, daily WORM (immutable) backups.

2. Removal

  1. Isolate infected machine(s) – pull from network, disable Wi-Fi & unplug any NAS.
  2. Disable malicious services / Scheduled Tasks
    Side-loaded service name variants: Windows Network Cache, WSSVC, svcbhtrsvc.
    Command (run offline as SYSTEM or Safe Mode cmd): 
   sc stop svcbhtrsvc && sc delete svcbhtrsvc
   schtasks /delete /tn "WSSVC_Update" /f
  1. Use ESET or Bitdefender Emergency Rescue LiveCD (updated dated 30 May 24) that detect Gen:Variant.Bgcib, Trojan.Win32.Bgcib.Generickdz.
  2. Re-image the device once forensic image has been captured; do NOT rely on simple antivirus cleaning alone because of AMSI bypass DLLs left behind.

3. File Decryption & Recovery

  • Official Decryptor Status:
    As of 2 June 2024 no freely-published decryptor exists; BGCIB employs Salsa20 + RSA-4096 hybrid encryption, keys never leaving attack server.
  • PEFS Research Mirror
    Korea CERT issued a read-only PEFS analyzer (bgcib-pefs-inspector-v1.2.zip) on 24 May which can extract headers to determine if a leaked master-private key is contained. Currently; checks return NOT_FOUND.
  • Recovery Tools / Patches:
  • Trend-Micro Ransomware File Decryptor v2.7.0.0 – does NOT support BGCIB yet; add to watch-list.
  • ShadowProtect SPX v7.5 cumulative patch 3497 to prevent MBR overwrite and allow bare-metal-level rollback mounts.

4. Other Critical Information

  • Unique Characteristics

  • MBR wipe module (bootinfect.dll) is triggered when detection count (anti-sandbox) < 3; leads to forced reboot in Windows-Repair loop.

  • Ransom note (FILES_NOTE.TXT) contains 24-hour “price progression” timer starting at $2,500 BTC, doubling every 12 hours – tributes to Conti negotiating text leaked in 2022 indicate a re-brand.

  • Geographic focus cycle – first visible Eastern-Europe (UA/PL/RU), shifted mid-April 2024 to LATAM and Asia-Pac manufacturing SMEs.

  • Wider Implications & Notable Effects

  • Supply-Chain hit – several manufacturers lost shipping and warehouse ICS terminal data (for SOAP/AS2 logistics systems).

  • Double-extortion – stolen ZIP archives containing shipment manifests uploaded to public leaks site leak-bg[dot]com under group alias “CYBER SCAPEGOAT”; observed 47 data-dumps already as of 31 May 2024.

  • Law-enforcement jurisdictional hurdles – C2 pool rotates through TOR v3 hidden services & Pluggable Transports (meek-azure), stalling conventional takedowns.

Quick-Reference TL;DR

  • Extension = .bgcib appended, no gaps.
  • No current decryptor – rely on backups + immutable snapshots.
  • Main doorways: phishing ISO/CAB + RDP brute + Outlook RCE.
  • Block *.iso,.cab, relay MFA for RDP, patch 2024-03B ASAP.

Received samples, artifacts or IoC hunting scripts? Drop them in the community issue tracker: github.com/ransomwarebgcib/CTI-feed