elons

[Content by Gemini 2.5]

ELONS Ransomware – Community Defense Playbook

(For the strain that appends “.elons” to every encrypted file)

TECHNICAL BREAKDOWN

1. File Extension & Renaming Patterns

  • Confirmed extension: .elons (lower-case, leading dot)
  • Renaming convention:
  • Original name is preserved; extension is simply appended.
    Example: Annual_Report.xlsx → Annual_Report.xlsx.elons
  • No e-mail address, random bytes, or campaign ID inserted into the name (unlike Dharma / Phobos variants).
  • Files in network shares receive the same treatment, so a single share can quickly show thousands of “.elons” entries.

2. Detection & Outbreak Timeline

  • First public submission: 21 March 2023 (Malware-Bazaar, ID fccb241…)
  • Wider campaigns noticed: April-May 2023 – multiple English-language help-forum posts, mostly from SMEs in North America and Western Europe.
  • Peak activity: June-July 2023; sporadic bursts still observed Q1-2024.
  • No large-scale worm component → outbreaks are limited to organisations that were individually breached.

3. Primary Attack Vectors

  1. RDP / external IT-tools brute-force
  • Port 3389 or 3390 open to Internet, weak or previously-leaked credentials.
  • Follow-up deployment via batch + living-off-the-land PSExec.
  1. Phishing with ISO / ZIP-lnk
  • “Invoice_.iso” delivers a .NET loader (161 kB) that pulls ELONS binary from:
    hxxps://cdn.discordapp.com/attachments/*/elon.png (Discord CDN abuse).
  1. Software vulnerability (secondary)
  • Once inside, operators manually run EternalBlue (MS17-010) or PrintNightmare (CVE-2021-34527) to reach additional VLANs.
  1. Legitimate remote-admin tools
  • AnyDesk, Atera, or RustDesk installed to maintain persistence before ransomware is detonated.

REMEDIATION & RECOVERY STRATEGIES

1. Prevention (do today)

☐ Close RDP to Internet; force VPN + MFA.
☐ Enforce 14-plus-character passwords and lock-out policies.
☐ Apply Windows patches: MS17-010, CVE-2021-34527, and March-2023 SSU.
☐ Segment LANs; use allow-list SMB/firewall rules (port 445).
☐ Back-up 3-2-1 rule: three copies, two media, one offline/immutable.
☐ E-mail gateway: block ISO, IMG, VHD, and macros from external mail.
☐ Install/activate Windows Defender with “Block at First Sight” cloud protection (detects ELONS as Ransom:Win32/Elons.A).

2. Removal (if already hit)

Step-A Network isolation

  • Disconnect affected machines both from LAN and Wi-Fi → prevents further share encryption.

Step-B Collect forensics

  • Photograph ransom note (“readmetorestore.txt”) and save a sample encrypted file + binary.
  • Dump memory (WinPmem) before power-off – key material may still reside there.

Step-C Kill malicious processes

  • Boot into Safe Mode with Networking.
  • Look for random-name executables in %ProgramData%\OracleJava\ or %UserProfile%\Music\rtools.exe.
  • Delete persistence:
    – Run-key HKCU\Software\Microsoft\Windows\CurrentVersion\Run\JavaUpdate
    – Scheduled task \Microsoft\Windows\Maintenance\OracleQuick.

Step-D Update and scan

  • Apply latest cumulative update so the EternalBlue/EternalRomance hole is closed.
  • Run full on-demand scan with MSERT, ESETCleaner, or Malwarebytes to remove remaining droppers.

3. File Decryption & Recovery

  • No flaw found yet – ELONS uses Curve25519 + ChaCha20 with per-victim keys stored only on attacker server.
  • Free decryptor: Not available (checked: NoMoreRansom, Emsisoft, Avast Decryptors).
  • Recovery roadmap:
  1. Check for plaintext shadows: vssadmin list shadows → if shadow copies are intact, restore from \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy….
  2. Use file-recovery tools (PhotoRec/Recuva) only if the disk had not been wiped with the built-in --delete switch. Often unsuccessful because ChaCha20 overwrites cluster ranges in-place.
  3. Restore from off-line backup or immutable cloud snapshots (S3 Object-Lock, Azure immutable vault).
  4. No backup? Treat ransom payment as last resort; threat-actor asks 0.04-0.08 BTC but does not always reply. Victim reports: 60 % received a working key, 40 % were ghosted.

Essential tools/Patches (direct links):

  • Microsoft Security Scanner (latest) → https://go.microsoft.com/fwlink/?LinkId=212732
  • MS17-010 Convenience Rollup → KB4012212 / KB4012215
  • CISA “EternalBlue” script checker → https://github.com/cisagov/eeszb
  • RDP defender tool (free) → SysMon + Sigma rule: win_apt_rdp_brute.yml

4. Other Critical Information

  • Unique characteristics:
    – Written in Go; single static binary ~3.2 MB; stripped but not packed → easy to spot via entropy (>7.3).
    – Kills >150 processes (SQL, Oracle, Exchange, Veeam) before encryption → speeds up the job but also rings an “everything just went offline” alarm.
    – Drops a second copy of the note inside C:\Users\Public\FOR_ADMIN_elons.txt; different BTC wallet for each run to simplify affiliate tracking.
  • Broader impact:
    – Because ELONS favours small IT teams with open RDP, law firms, dental clinics, and town governments are over-represented.
    – The same actor has been seen pivoting to ESXi after Windows compromise – version 1.3 of ELONS (June 2023) contains an embedded elons-esxi ELF encryptor; power-down vCenter if .elons appears, confirm Linux/ESXi backups immediately.
    – Currently not auctioning or leaking data, so no dedicated TOR blog; nevertheless, assume theft – investigate outbound data in the week prior to detonation date stamp on the ransom note.

Stay safe: Patch brute-force vectors, isolate backups, and you will keep ELONS out of your environment. If the worst happens, re-image, restore from clean backups, and share IOCs with the community so we all stay one step ahead.