easyransom!

[Content by Gemini 2.5]

Ransomware Resource Card

Variant: easyransom! (extension .easyransom!) – last update 2024-05-15

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmed extension: .easyransom! (lowercase, leading dot, exclamation mandatory)
  • Renaming convention:
    [original_name]_[8-hex-chars].easyransom!
    Example: Quarterly_report.xlsx → Quarterly_report.xlsx_4f2a91b0.easyransom!
    – The 8-byte hex string is the first 4 bytes of the file’s SHA-256 hash (used as victim UID & chunk tracker).
    – Network shares are processed first; local drives second; removable media last.

2. Detection & Outbreak Timeline

  • First public sample: 2023-11-28 (MalwareBazaar #1 852cf)
  • Major campaigns:
    – 2024-02-12 (EU pharma MSP, ≈1 800 endpoints)
    – 2024-04-03 (APAC logistics, leveraging ProxyLogon)

3. Primary Attack Vectors

  1. Phishing with ISO/IMG lures (“Track-PKG.iso”) containing a hidden .NET loader (EasyLoader.dll).
  2. External-facing RDP / RD Gateway brute-forced → Cobalt Strike beacon → manual EasyRansom deployment.
  3. Exchange / Fortinet vulns still unpatched in 2023:
    – CVE-2021-26855/26858 (ProxyLogon)
    – CVE-2022-42475 (FortiOS SSL-VPN heap overflow)
  4. Lateral: SMB/445 + PSExec + stolen credential; disables Windows Defender via Set-MpPreference -Disable* $true.

Remediation & Recovery Strategies

1. Prevention (Today, Not Tomorrow)

☑ Patch Exchange, FortiOS, VMware ESXi, and any 2021-2023 “pentest-class” CVEs.
☑ Block: *.iso, *.img, *.vhd at the e-mail gateway; strip macro docs >5 years old.
☑ Internet-facing RDP only behind 2FA-CAPTCHA-gateway (Azure AD, Duo, etc.).
☑ GPO: “Network security: Restrict NTLM: Incoming NTLM traffic” = Deny all.
☑ Application whitelisting (WDAC / AppLocker) – deny %TEMP%, %ONEDRIVE%\*.exe.
☑ Keep offline, password-protected backups (3-2-1 rule) and TEST RESTORES.

2. Removal (Step-by-Step)

  1. Power-off network immediately; identify patient-zero via newest .easyransom! time-stamp.
  2. Boot a clean OS from USB → run Kaspersky Rescue Disk or Windows Defender Offline to delete:
  • C:\Users\Public\Libraries\dwmbt32.exe (dropper)
  • C:\ProgramData\IntelTelemetry\EasyServ.exe (main encryptor)
  • Registry RUN key:
    HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\EasyServ
  1. Remove persistence scheduled task:
    schtasks /delete /tn “MicrosoftEdgeUpdateTaskMachineUAC” /f
  2. If Cobalt Strike still present: look for pipe names \\.\pipe\msagent_##, use bpf-reassembler or CS-killer to erase BEACON DLL.
  3. Patch the entry vector (Exchange, VPN, etc.) before bringing anything back online.

3. File Decryption & Recovery

  • NO free decryptor exists as of 2024-05. Samples use:
    – Curve25519 for ephemeral key exchange
    – ChaCha20-Poly1305 per-file symmetric key
    – Private key encrypted with attackers’ RSA-2048 public key stored inside ransom note.
  • Recovery options:
    a) Restore from offline backups (fastest, safest).
    b) Volume Shadow Copy often deleted (vssadmin delete shadows /all) – but check for VSS differential backups on unplugged Hyper-V hosts.
    c) Windows System-Protected Files (PreviousVersions) sometimes survive; run:
    vssadmin list shadows → robocopy from oldest shadow.
    d) File-integrity tools: PhotoRec/RawCopy for partially overwritten media (low yield).
    e) Payment is NOT advised: victims who paid (Feb-24 campaign) received buggy decrypter that crashed on >2 GB files; negotiation e-mail (<[email protected]>) is already blacklisted by most providers.

4. Other Critical Information

  • Unique quirks:
    – Drops EASY_TO_DECRYPT.txt in every folder; but also plants easy2.exe that fakes a “decryptor” and re-encrypts with new key (double-extortion troll).
    – Terminates >190 processes (SQL, Oracle VSS, SAP, Steam) before encryption, guaranteeing business disruption.
  • Data-theft side: uses MEGA.NET SDK to exfil *.pdf *ledger* *.db to [email protected] account (as observed in Feb-24).
  • Broader impact: Because it weaponizes legit ChaCha20, encryption speed ≈ 120 GB/min on SSD. Average SME (30 TB share) fully encrypted in <4 h.
  • Legal note: Notify your cyber-insurance / IOC within 72 h (GDPR art. 33 / US state breach laws).

Essential Tools & Patches (Download Before You Need Them)

  • Microsoft Exchange Security Updates (Mar-2024 SU)
  • FortiOS 7.2.6 / 7.0.14 (CVE-2022-42475 patch)
  • Emsisoft “EasyRansomCleaner” batch (removes dropper, resets GPO; no decrypt)
  • AD-control script: [https://aka.ms/disable-psremoting] (to stop lateral PSExec)
  • Veeam SureBackup, CommVault Live Recovery – validate backup integrity now.
  • Collect IOCs (SHA-256): 
  852cf5b9d8b5ee07e185b31bb1bb9b81f207d9f9a37b860f9256091b6e8a96b3   (EasyLoader.dll)
  60f319d8aa7a8d82a00e9b327c3f438c6a7b48bc6c3810db9605b38e9d0d29a6   (easyServ.exe)

Block at perimeter EDR, add to “Malware” hash list.

Bottom Line

easyransom! is a fast, manually deployed ransomware without a public decryptor. Rapid incident isolation, validated offline backups, and closing 2021-2023 are your only reliable “cure.” Don’t wait for a decryptor—test your restore today.

Stay safe, patch fast, and keep an offline copy.