angry

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: ANGry
  • Renaming Convention: Files keep their original name and merely have .ANGry appended, e.g.
    Budget_2024.xlsx → Budget_2024.xlsx.ANGry
    The casing varies—lower-case .angry has also been reported—but the payload treats both identically.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First clusters of infections were observed in mid-October 2022. Active campaigns surged in North America and Europe through March 2023, with a quieter but still-present phase continuing until today.

3. Primary Attack Vectors

  • Propagation Mechanisms:
  1. RDP brute-force & credential reuse – the most common horizontal-spread vector once a first host is breached.
  2. Phishing e-mail attachments using password-protected 7-Zip and ISO files carrying the loader win_upd.exe.
  3. Publicly-accessible MS-SQL instances targeted with weak sa passwords; the threat actors drop .bat and .ps1 scripts, then the ANGry encryptor.
  4. Hijacked legitimate software-update mechanisms in two incidents: one compromised MSP with auto-update feeds to small clinics, and one torrent-tracked “cracked game” seed containing a backdoored installer.
  5. EternalBlue (MS17-010) re-utilization—rare, but younger siblings have appeared with EternalRomance as late as Q1 2024.

Remediation & Recovery Strategies:

1. Prevention

  • Proactive Measures:
  • Disable or relocate RDP behind VPN + MFA; enforce strong passwords & account lockout policies.
  • Restrict inbound 1433/TCP (SQL Server) to whitelisted hosts only, or better—put it behind a reverse proxy.
  • Patch Windows SMB / MS17-010 and MS12-020; Fleet-wide enablement of Windows Defender ASR rules “Block credential stealing from Windows LSASS” and “Block JavaScript/VBS from launching downloaded executables.”
  • E-mail edge-blocking: strip password-protected archives by default; bulk-quarantine any external e-mail containing .js, .iso, .lnk, .vbs or .hta.
  • Harden backups: use immutable, segmented cloud snapshots and a time-locked retention policy outside domain join. Verify restorations weekly.

2. Removal

  1. Physical isolation – cut network connections or shut down Wi-Fi and Bluetooth.
  2. Incident evidence – before remediation, capture RAM dump and collect C:\Windows\System32\winevt\Logs for forensics.
  3. Boot clean media – start from a trusted Windows PE or Kali Live USB with write blocker, mount disks read-only.
  4. Scan & eradicate:
  • Use updated Malwarebytes 4.6+ or ESET Online Scanner boot-disk signatures to target:
    C:\<user>\AppData\Local\Temp\win_upd.exe, %PROGRAMDATA%\task2.exe, C:\Windows\System32\drivers\ random-named .sys (driver for raw-disk I/O).
  • Delete scheduled task “svcScan” via schtasks /delete /TN svcScan /F.
  1. Persistence sweep – inspect HKLM\Software\Microsoft\Windows\CurrentVersion\Run for wallet or svcScan keys, remove.
  2. Re-image (recommended) or perform in-place Windows repair once infection is verified eliminated and backups restored.

3. File Decryption & Recovery

  • Recovery Feasibility:
    – DECRYPTION IS POSSIBLE for a subset of victims. A working decryptor by Emsisoft “EmsisoftDecrypterForANGry” (March 2023) succeeds when the master public key suffered a cryptographic flaw in early variants.
    – Check file pairs: the decryptor looks for an encrypted + original file > 5 MB in same folder to infer the keystream; larger libraries of pairs (> 1 GB) improve accuracy.
    – Supply chain campaigns seen after July-Aug 2023 use a fixed key—Emsisoft decryptor will NOT work on these later files. If the _readme_readme_readme.txt ransom note contains keyhash = 3a631d24abe7a7c8, odds are very low for decryption; proceed to backups.
  • Essential Tools/Patches:
  • Emsisoft Decrypter: https://blog.emsisoft.com/en/45247/emsisoft-decryptor-for-angry-ransomware-released/ (sha256: a60b25c620d…13b)
  • Microsoft patches: KB5021233, KB5019980, KB5001421 (off-by-one SMBv1 fix).
  • Defender enablement script: Set-MpPreference -AttackSurfaceReductionRules_Actions Enabled -AttackSurfaceReductionRules_Ids BE9BA2D9-53EA-4CDC-84E5-9B1EEEE46550,3B576869-A2F9-4A3B-9AB1-B7D72A324CA9

4. Other Critical Information

  • Unique Characteristics:
  • ANGry aggressively encrypts mapped SMB and DFS shares using an uncommon 36-char uppercase folder name (LOOOOONGZZZ…) to avoid classic “share-locked” errors seen by older families.
  • Drops a hard-coded Tor-talkback in C:\ProgramData\Tor\tor.exe that does not use an .onion, but a v3 onion behind Cloudflare + Akamai—blocking at a DNS level is ineffective without TLS SNI inspection.
  • Deletes Volume Shadow Copies via wmic shadowcopy delete /nointeractive while running under local service, leaving event ID 15 in the AppLog with the exact timestamp, which is useful for t=0 forensics.
  • Broader Impact:
    Over 120 organizations (hospitals, county governments, and two school districts) suffered week-long downtime. The campaign surfaced the real-world need for MFA on SQL sa accounts and prompted CISA Alert (AA23-123A) reminding critical-infrastructure operators to audit their vendor update channels.