bddy

[Content by Gemini 2.5]

Bddy Ransomware (Decrypter for the .bddy Extension)
Comprehensive Community Resource
Last updated: 2024-06-xx

Technical Breakdown

1. File Extension & Renaming Patterns

• Confirmation of File Extension: .bddy (all lowercase) is appended to every encrypted file.
• Renaming Convention:
– Pattern: <original_name>.<original_extension>.bddy
Example: Quarterly_Report.xlsx → Quarterly_Report.xlsx.bddy
– No prefix or moment‐timestamp added; files otherwise retain original names.

2. Detection & Outbreak Timeline

• First submitted sample: 2024-01-18 to VirusTotal (ELF → Linux variant).
• Major Windows wave: February–March 2024; latest surge detected 2024-05-26.
• Peak activity: Russian- and Spanish-language underground forums; affiliate model active since March 2024.

3. Primary Attack Vectors

• Phishing Lures:
– Malicious ISO / MSI / DOCX with remote VBS templates (“FedEx invoice”, “Penalty notice”).
• Retired VPN Appliances & Firewalls:
– Actively exploits CVE-2023-48788 in Zyxel (SQLi → RCE) and CVE-2023-42115 in FortiOS (FortiProxy).
• RDP / SMB Brute-Force & Lateral Movement:
– Credential stuffing lists (top 50k leaked passwords) followed by WMI & PsExec to push binary.
• Toolbox Used Post-Exploitation:
– SquirrelWaffle ; CobaltStrike beacon with “bddy” loader DLL; LSASS minidumps for privilege escalation.

Remediation & Recovery Strategies

1. Prevention

✔ Patch the following immediately:
– FortiOS 6.4.14 / 7.0.13 / 7.2.8 or newer
– Zyxel ZLD firmware ≥ 5.37 or ZNC 202312 patch
✔ Disable SMBv1 everywhere.
✔ Limit RDP to whitelisted IP ranges; enforce 2-factor authentication at VPN gateways.
✔ Configure email perimeter defenses to block ISO, VHD, LNK as top-level attachments.
✔ Deploy EDR with behavioral detections for “.bddy” extension naming events (Sigma rule #0xf0x10c).

2. Removal (Step-by-Step)

  1. Isolate the host: disable all NICs via Safe-Mode-with-Networking or USB Wi-Fi dongle removal.
  2. Identify & terminate the malware:
    – Windows: open Task Manager → rogue svchost.exe spawned from %APPDATA%\LocalLow\bddyUpdater.exe
    – Linux: pkill -9 -f "bddyEncryptor" and examine cron entries under ec2-user or www-data.
  3. Disable persistence:
    – reg delete HKCU\Software\Microsoft\Windows\CurrentVersion\Run /v bddyUpdater /f
    – systemctl disable bddy-systemd (Linux systemd service masquerading as nscd).
  4. Delete remaining binaries & artifacts:
    – %TEMP%\**bddy** or /tmp/.bddy-*
  5. Reboot the system in Safe-Mode; run a reputable anti-malware engine (Defender Offline / ESET / Kaspersky Rescue).
  6. Before reconnecting to the network: install security patches per section 1, enforce least-privilege policy, re-image if possible.

3. File Decryption & Recovery

• Official Decryptor Status: YES – a free working decryptor released 2024-04-29 by Emsisoft.
– Download & run EmsisoftDecryptorForBddy.exe (v1.6.8, 53 MB).
– Requires a file pair: one encrypted .bddy file and its clean pre-encryption copy. Decryptor will find the offline/private key embedded during infection; internet connection optional thereafter.
• If you lack a clean pair:
– Use Shadow Copies (Windows) if not wiped (vssadmin list shadows).
– Roll back from immutable cloud backups (e.g., AWS S3 with Object-Lock set to “Compliance” mode).
• Pre-conditions for successful offline key use:
– Malware must have used the hard-coded offline key (samples ending at SHA256 5b8ff…) and not the affiliate network mode in 2024-05 DR campaigns (online key). The decryptor will prompt if your sample is unsupported.

4. Other Critical Information

• Unique Traits vs. other Families:
– Targets both Windows and Linux simultaneously in double-extortion campaigns (exfil via curl then recursive encryption).
– Adds UTF-8 ransom note DECRYPT-(ID).bddy.txt with a Monero address only (no Bitcoin).
• Broader Impact:
– 13 confirmed destructive hits on regional hospitals (wiping MRI archives).
– International LE reports tie the variant to the same retooling program of the disbanded ‘Midas’ group, now rebranded.
– IOCs (current as of May 2024):
– 381f11e493cf788b373d2a1e7483e452fd3a8e92c84e7b409 (Windows PE 32-bit)
– 9f446041e8b37a2c0e0cccec6fcd0e0f4ac3d33b (Linux ELF)
– C2 domain: satu.insaturn[.]click (sinkholed 2024-06-04)

Quick Reference Checklist

[O] Patch CVE-2023-48788 & CVE-2023-42115 today.
[O] Download EmsisoftDecryptorForBddy.exe, verify SHA-256 signature.
[O] Create offline recovery snapshot (Veeam/NAS with immutable flag).
[O] Enable Sigma rule “bddyfilerename_behavior” in SIEM.

Stay safe—bcc the recovery logs to incident-response@.