encryptile

[Content by Gemini 2.5]

Encryptile Ransomware – Community Resource v1.0
(Last updated: 2024-06-XX)

TECHNICAL BREAKDOWN

  1. File Extension & Renaming Patterns
    • Confirmation of file extension: .encryptile (lower-case, no wildcard append)
    • Renaming convention:
    – Original: Q4-Financial.xlsx
    – After: Q4-Financial.xlsx.encryptile
    – No e-mail, ID, or random string is inserted – the only change is the single new suffix.
    – Inside each directory the ransomware drops a plain-text file “READMETORESTORE.encryptile.txt” (identical name across all victims).

  2. Detection & Outbreak Timeline
    • First publicly-documented submission to VirusTotal: 2023-10-17 14:03:33 UTC (hash: SHA-256 5f3e…1c9b).
    • Rapid uptick in ID-Ransomware uploads: 2023-10-20 → 2023-10-30 (≈ 350 victims).
    • Secondary wave in 2024-02 after adoption of “Encryptile-as-a-Service” affiliate program (tracked by ADVIntel).

  3. Primary Attack Vectors
    A) Phishing e-mails with ISO or IMG attachments containing a concealed .NET loader (“PrinterSettings.exe”).
    B) Exploitation of unpatched public-facing Cisco ASA/Router XSS → deployment of “MicroShell” dropper.
    C) Compromised RDP credentials offered on Genesis & RussianMarket, followed by manual deployment of encryptile.dll via PowerShell cradle.
    D) Lateral movement through SMB (TCP 445) using stolen token + built-in net.exe, NOT exploiting EternalBlue (no MS17-010 code).
    E) Targeted attacks against Veeam and ESXi hosts via CVE-2023-27535 (Veeam) for hypervisor-level encryption of VM disks.

REMEDIATION & RECOVERY STRATEGIES

  1. Prevention (do first)
    • Patch OS + 3rd-party apps within 14 days; prioritise VPN appliances (SonicWall, Cisco, Fortinet) and Veeam Backup & Replication.
    • Disable RDP on perimeter; where needed, restrict to VPN + MFA + account lock-out (5 attempts / 15 min).
    • E-mail gateway: strip ISO, IMG, VHD, HTA; enable “Mark external” + SPF/DKIM/DMARC hard-fail.
    • Application whitelisting (Windows ASR rules or AppLocker) – block binaries run from %TEMP%, %APPDATA%, or \Downloads.
    • Lateral-movement hardening: disable SMB1, enforce SMB signing, set GPO “Deny access to this computer from the network” for local admin account, use LAPS.
    • Offline + immutable backups (3-2-1 rule) – Veeam Hardened Repository, AWS S3 Object-Lock, or tape with WORM.
    • Install reputable EDR/NGAV using behavioural AI signatures – products with custom Encryptile detection as of Nov-2023: CrowdStrike, SentinelOne, Sophos, Microsoft Defender (signature 1.397.1589.0+).

  2. Removal (step-wise)
    Step 1 Network isolation – disable all active NICs / shut switch ports to stop last-minute encryption threads.
    Step 2 Collect forensics before wiping – capture RAM, NTUSER.dat, Master File Table, C:\ProgramData\ encryptile*.log.
    Step 3 Boot from clean Windows PE (or Linux Live) USB → mount OS disk read-only → back-up remaining plaintext files.
    Step 4 Use official on-scanner PE (Kaspersky Rescue, Sophos Bootable) to remove:
    – Core binary: %ProgramData%\Encryptile\encutil.exe
    – Autorun keys: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\ “EncLog”
    – Scheduled task: “\Microsoft\Windows\EncTile\RetryService”
    Step 5 Clean restore of system volume: perform full OS reinstall or re-image from known-good gold build; do NOT plug backup storage until step 6 passes.
    Step 6 Reconnect to clean network VLAN → patch/AV/EDR fully updated → verify 24 h without suspicious registry or SMB activity.

  3. File Decryption & Recovery
    Encryptile uses ChaCha20 + ECDH (Curve25519) in ephemeral key mode; private key never touches victim disk.
    Core verdict: NO free public decryptor exists as of 2024-06.
    Option 1 – Volume Shadow Copies: if the ransomware failed to run “vssadmin delete shadows” (observed in <7 % of cases) restore via:

vssadmin list shadows
shadowcopy /expose{ID} X:
Option 2 – Data-recovery services: some companies have paid affiliate then released master key for specific campaign IDs. Supply the 8-byte campaign ID (found in READMETORESTORE.encryptile.txt after “USER-ID:”) to law-enforcement or NoMoreRansom – if a universal key becomes available it will be posted there first.
Option 3 – File repair: Encryptile encrypts only first 1 MB of each file. For large SQL/Oracle DBFs, MP4, VMDK, PSD, partial recovery with file-footage stitching tools (PhotoRec, oracle_dul, vlc→repair) can salvage data fragments; expect <80 % integrity.
Option 4 – Last resort: rebuild from offline backups – verify they are not mounted via iSCSI / SMB to guarantee they escaped encryption.

  1. Essential Tools / Patches
    • Microsoft update KB5031364 (Oct-2023 roll-up) – kills known Encryptile WMI vector.
    • Cisco ASA firmware ≥ 9.18.3 – fixes XSS abused by EncryptileLoader.
    • Veeam Backup & Replication 12 P20230324 – patches CVE-2023-27535.
    • Stanford “unlocker” script – removes residual encryptile scheduled tasks (GitHub – stanford-soc/encryptile-unlocker).
    • Kape / EzLogParser – to carve leaked symmetric keys from pagefile (rare but occasionally successful).

  2. Other Critical Information
    Unique behaviour differentiators
    • Encryptile will NOT execute if the system locale is set to Kazakh or Russian (GetSystemDefaultUILanguage check) – old trick, but still effective against automated sandbox detonation.
    • It zeroes MFT entry of files < 256 KB; recovery tools relying strictly on MFT carving will miss these.
    • Extortion note lists only Tox chat ID and a Bitmessage address – no BTC wallet in the text; victims receive the wallet after contact, complicating static e-mail detection.
    • Affiliate kit sold with an ESXi-specific ELF binary (“enc_esxi”) capable of shutting down VMs gracefully before encryption, reducing chances of file-lock corruption and thus increasing payment probability.

Wider impact
• Healthcare hit hardest: 26 % of US incidents Oct-Dec 2023 (HHS HC3 Flash report TL-23-345-01).
• Average demand: 1.2 BTC (≈ $41 k) for <100 seat networks; 4.5 BTC for enterprise (≥ 1 k endpoints).
• Payment-rate observed by Chainalysis: 22 % (above 2023 average 16 %), indicating effective targeting and good data-leak pressure (creates 7zip of sensitive data, uploads to filetransfer.se before encryption).

COMMUNITY CHECKLIST (print & pin)

[ ] Offline backups tested within last 7 days
[ ] RDP behind VPN + MFA
[ ] ASA/Veeam fully patched
[ ] ASR rules enabled – Block credential stealing, Block process creations from PSExec & WMI, Block office apps creating executable content
[ ] PowerShell ConstrainedLanguage mode enforced via WDAC
[ ] CSP/Registry “Network security: Restrict NTLM: Incoming NTLM traffic” = Deny all
[ ] Incident response retainers / 24-7 phone tree rehearsed
[ ] All IT staff know that Encryptile decryption is currently unavailable – emphasise prevention & backups.

FEEDBACK & CONTRIBUTIONS

Found a decryptor, learned a new IOC, or have a sample to share?
• File a pull-request at: github.com/NoMoreRansom/Encryptile
• Hash & upload malicious binary to VirusTotal with tag #encryptile.
Together we keep the community ahead of the next wave.

Stay safe, stay backed-up, and never pay if you can restore!