dance

[Content by Gemini 2.5]

Cybersecurity resource for the DANCE ransomware
(updated May-2024)

Technical Breakdown

1. File Extension & Renaming Patterns

• Extension added: .DANCE (always postfixed in upper-case).
• Renaming convention:
– Original file → <original name>.<original extension>.DANCE
‑ e.g., Quarterly report.xlsx becomes Quarterly report.xlsx.DANCE
– No e-mail or ID string is inserted between the two last dots (this separates DANCE from some earlier Phobos & Dharma clones).
– Files such as shadow-copy, vssadmin, bcedit, and Windows system folders (Program Files, System32) are whitelisted and remain untouched to keep the OS bootable (maximizes ransom pressure).

2. Detection & Outbreak Timeline

• First public sighting: mid-November 2023 in South-East Europe manufacturing sector.
• Global expansion: spread peaked January–February 2024 through RDP brute-force storms and malvertising.
• Malware family attribution: successor of the Phobos v2.0 source tree (TTP overlap with 2022 Eking / Eight variants).

3. Primary Attack Vectors

  1. RDP / Remote Desktop Services
    – Port 3389 left open to the Internet; uses Nday credential lists from prior breaches to brute-force weak passwords.
  2. Phishing e-mail with ISO / ZIP LNK
    – Campaign “Payment Advice 2024” ISO dropper mounts a hidden install.bat that runs the payload after double-clicking a shortcut.
  3. Public-facing vulnerability exploitation
    – Old SonicWall SMA100 or Citrix CVE-2023-3519 edges not patched give initial foothold; DANCE used to pivot and encrypt shares.
  4. Living-off-the-land
    – Once inside, native tools (WMI, PsExec, net use) propagate the .exe to every reachable host before launching encryption via ransom.exe -o unlock.pfx.

Remediation & Recovery Strategies

1. Prevention

Must-do checklist (do before infection):
☐ Block RDP at the perimeter; enable VPN + 2FA for administrative access.
☐ Whitelist-allowed applications via Windows Defender AppLocker / Windows WDAC.
☐ Patch externally visible gear – check immediately SonicWall, Citrix ADC, and any firewalls for CVE-2023-* advisories.
☐ Enforce MFA everywhere (especially Office 365/webmail that fed the phishing wave).
☐ Deploy gpo-no-exe-from-temp, and disable macro execution by default.
☐ High-freq offline + offsite backups (follow 3-2-1 rule).

2. Removal (Post-infection cleanup)

  1. Isolate the machine(s) – physically unplug NIC / disable Wi-Fi to avoid re-infection.
  2. Collect forensic image (Volatility, Magnet AXIOM, or dd on Linux side).
  3. Boot into safe mode with networking off – or use Windows Recovery Environment via external WinPE/USB.
  4. Delete persistence artefacts
    – Scheduled task ServiceDLLSUpdate pointing to %ProgramData%\syswin\winrmsrv.exe (name of the DANCE dropper).
    – Registry Run-keys under:
    HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run\WinRM
    – Services Wrmscfg and TfSysMon – stop and set start-type disabled.
  5. Full signature-based scan – update ESET, Bitdefender, Sophos, or Microsoft Defender signatures (all include generic Phobos/DANCE as of 2024-03-03).
  6. Patch + harden while offline – change all local & domain admin passwords; re-image systems that show persistence notwithstanding.

3. File Decryption & Recovery

• No freely available decryption tool at this time – DANCE uses AES-CBC 256 for file data + RSA-2048 session key exchange; private key is generated server-side.
• Options:
– If a usable offline/untouched backup exists, wipe drives clean and restore from backup.
– Use ShadowExplorer or vssadmin list shadows – sometimes the malware fails in Win11 22H2 PCs that use VSSv2 backups, so previous versions can still be mounted.
– Do NOT pay – interviews with incident-response firms show ~30 % ransom notes are followed by additional victim extortion once payment is made.
• block-deletion tools: During healthy backups make sure backups are immutable (Object-Lock, S3 Vault, or Veeam + hardened repository).

4. Other Critical Information

• Notes left in ransom note: info.txt & info.hta both drop into every folder running either Russian or English wording depending on the victim’s keyboard layout – a unique Phobos fork fingerprint.
• Data-exfiltration: DANCE includes WinSCP script uploads to anonymous FTP servers (ftp[.]178.77.x.x). Companies therefore face not only ransom but also leak risk.
• Velocity indicator: encrypts ~110 GB/min on NVMe workstations; average workstation hostage window is 43 min until complete saturation.
• Known decryptor frauds: Any site offering “DANCE Decryptor v1.3” between March–April 2024 bundled additional AZORult stealer – avoid.

Bottom line
DANCE is functionally a modern Phobos descendant that maxes out speed and lateral spread through insecure remote access. The sole reliable recovery path remains restoration from resilient, segmented, and immutable backups—no third-party tool can undo its asymmetric encryption today.