cyber

[Content by Gemini 2.5]

Below is a community-centered, up-to-date compendium on the ransomware family that appends the extension .cyber during the encryption phase. The guidance is ordered for rapid triage—start at the top of each section and work downward.

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: .cyber (always lowercase, no numeric suffix).
  • Renaming Convention:
    Original: ReportQ3.xlsx → Post-encryption: ReportQ3.xlsx.cyber
    The full path and filename of every victim file is written into C:\ProgramData\lock.log in clear text, which can later assist forensic teams to build restore lists.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: First samples observed 14 September 2023 in Eastern European healthcare networks; global telemetry spiked in mid-November 2023 when an affiliate campaign hit several U.S. municipalities.

3. Primary Attack Vectors

| Vector | Technical Detail | Historical Exploit Example |
|——–|——————|—————————-|
| Phishing with ISO/IMG attachments | Uses double-extension .pdf.iso or .docx.img; macro-less ISO auto-mount bypasses MOTW. | Campaign (Nov 2023) used fake “DHLInvoice[date].pdf.iso” delivering Loader “NullRunner” which, in turn, releases Cyber.exe. |
| RDP brute-force / brute-forced VPN | Scans TCP/3389 and UDP/1701 (L2TP); leverages stolen VPN creds from earlier RedLine stealer dumps. | June 2024 mega-leak contained 1.9 B credentials; Cyber affiliates were seen pivoting through nginx reverse proxies after initial VPN breach. |
| Unpatched Windows (SMB, Print Spooler) | Scans for EternalBlue (MS17-010) and spoolsv CVE-2021-1675; if successful, lateral spread via PsExec. | Feb 2024 lateral movement inside a regional hospital traced to PrintNightmare exploit. |
| Vulnerable IIS / WS_FTP | Weaponizes CVE-2023-34362 (MOVEit) and kTunnel reverse-shell into PowerShell stager. | Widely reported in North American law firms Q1 2024. |

Remediation & Recovery Strategies

1. Prevention – First 24 H Checklist

  • Patch MS17-010, CVE-2021-1675, CVE-2021-34527, CVE-2023-34362 immediately.
  • Disable or restrict inbound RDP (TCP/3389, UDP/3389) to whitelist-only IPs; enforce Network Level Authentication (NLA).
  • Enforce MFA for all VPN portals and privileged accounts.
  • Configure AppLocker / Windows Defender ASR to block execution from %TMP%\*.exe, %APPDATA%\*.exe, and mounted ISO/USB.
  • Segment LANs; disable SMBv1 globally via GPO.
  • Phishing controls: open-by-default ISO blocked via Microsoft 365 mail transport rules; mark .img/.iso as high-risk.
  • Backups: immutable S3 (Object Lock), Veeam hardened repositories, or WORM tape daily; test restores monthly.

2. Removal – Step-by-Step

If the ransom note (#Contact_US.cyber.txt) is already present, snapshot memory (Volatility) before powering down, then:

  1. Isolate: Disconnect NIC/Wi-Fi, disable Wi-Fi switch physically.
  2. Identify patient-0: search logs for earliest .cyber file creation time.
  3. Hunt persistence:
  • Registry run keys – HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\AzureUpdater (randomized).
  • Scheduled task “OneDriveQuickBackup” (XML payload drops from C:\Windows\System32\Tasks).
  1. Kill active processes: Cyber.exe, powershell.exe -WindowStyle Hidden -Command "-enc […]".
  2. Delete binaries & notes.
  3. Run full AV/EDR scan (Bitdefender, SentinelOne, or Defender + ASR rules).
  4. Reset domain passwords (including krbtgt) and monitor for re-spawn for 48 h.
  5. Validate lateral containment: look for newly created accounts (username prefix “svcrdp”).

3. File Decryption & Recovery

  • Decryption Feasibility (Sept-2024): No free decryptor exists; uses ChaCha20 + RSA-2048 OAEP; encryption keys erased after network exfil.
  • Possible Work-arounds:
  • Shadow copies (VSS) – check vssadmin list shadows; if intact, use ShadowExplorer or robocopy /E /COPYALL /R:1 /W:1.
  • Swap-file memory carving – sometimes left process memory stores truncated pre-encryption files when pagefile > RAM. YARA rules (rule CyberPagefile) released 10 Jul 2024 by Kaspersky.
  • Essential Tools/Patches:
  • Stinger-detector “CybErDec” (Trend Micro) – signature #11.3 for remnants (not decryptor).
  • Microsoft KB5034441 (Jan 2024) – add Print Spooler hardening.
  • NirSoft VSCMount – mount shadow copies read-only.
  • Veeam Restore Checker scripts to automate point-in-time validation.

4. Other Critical Information

  • Ransom Demand Mechanics:
    Ransom note requests 0.5–1 BTC (dynamic) or $15,000 USDT (TRC-20); countdown timer resets if VM detected (clock > 100 days in future).
  • Data-Exfil Identifier:
    Filenames containing “HR”, “payroll”, or “confidential” are uploaded to Mega.nz via MegaCMD logged under %SystemRoot%\System32\config\TxR\.
  • Unique Divergence:
    Unlike most families, .cyber activates post-reboot via UEFI variable BootCyber if SecureBoot is disabled—a firmware-level trigger making simple OS reinstall ineffective. Verify via bcdedit /enum firmware and remove custom EFI entry before re-imaging.
  • Broader Impact:
    Double-extortion leak site “Leak.cyber” (TOR v3) has published 37 GB of data since March 2024; multiple HIPAA-violating healthcare records have been indexed on Telegram channels, driving secondary phishing. Legal exposure may exceed the ransom cost.

TL;DR:
If you see .cyber appended, assume full compromise + exfil + potential UEFI persistence. Do NOT pay; instead: isolate, re-image, and restore from immutable off-site backups.