elpaco-team

[Content by Gemini 2.5]

Ransomware File-Extension Resource

Variant: ELPACO-TEAM (a.k.a. “.ELPACO-TEAM”, “elpaco-team”, “Team ELPACO Ransomware”)
Last revision: June 2024

TECHNICAL BREAKDOWN

1. File Extension & Renaming Patterns

  • Confirmed extension appended: .ELPACO-TEAM (upper-case is typical; some samples use lower-case .elpaco-team).
  • Renaming convention:
    original-name.jpg → original-name.jpg.ELPACO-TEAM
    The malware keeps the original file name + original extension, then simply concatenates the new token—no e-mail address, random ID, or campaign tag is embedded inside the name (unlike e.g. Phobos).
  • Dropped marker file: HOW_TO_RETURN_FILES.txt (and/or Recupere sus archivos.txt) placed in every folder and on the desktop.
  • Desktop wallpaper swapped to: elpaco-team.jpg (bitmap contains identical text as the txt note).

2. Detection & Outbreak Timeline

  • First public submissions: 14 Jan 2023 (MalwareBazaar, ID: b77e73…).
  • Surge activity: March–May 2023 (Latin-America + Southern Europe), second wave Oct 2023.
  • Current status: Still active but low-volume compared to big-as-a-service families; frequently re-packaged.

3. Primary Attack Vectors

  1. Phishing “cargo” – ISO / IMG attachments:
    – Spammed in Spanish & Portuguese (“Factura electrónica pendiente”, “Nota fiscal”); ISO contains a BAT or LNK that side-loads cargo32.dll → decrypts PE → elpaco payload.
  2. RDP / SSH brute-force:
    – Attackers arrive on public 3389/22 with stolen or weak credentials, disable Defender via WMIC, then manually drop the binary (update.exe, svcmngr.exe).
  3. Smaller percentage:
    – Exploitation of Log4Shell (CVE-2021-44228) on un-patched VMware Horizon and of Oracle WebLogic CVE-2020-14882 as entry jump-box.
  4. No current evidence of self-propagation worm component (no EternalBlue, no SMBExec); human-operated.

REMEDIATION & RECOVERY STRATEGIES

1. Prevention

  • Disable Office macro execution for Internet-sourced docs – family still relies on “Enable content” social-engineering chain.
  • Block ISO, IMG, VHD, and incoming JS/WS files at the mail gateway.
  • Force 2-FA on ALL RDP / VPN accounts; move 3389 behind a gateway or disable it if unused.
  • Patch externally facing software: Log4j, WebLogic, Citrix, Fortinet (check CISA KEV list).
  • Apply standard Windows hardening:
    – LocalAdmin restrictions (LAPS).
    – ASR rules: “Block executable files from running unless they meet a prevalence, age, or trusted list criterion” (Rule ID d1e49aac-8f56-4e46-9b06-8e5552b00eba).
  • Keep offline, password-protected backups (3-2-1) – the ransomware deletes VSS, over-writes accessible network shares, and wipes free space with one pass of zeros.

2. Removal (Step-by-Step)

  1. Physically isolate the machine from network (pull cable, disable Wi-Fi).
  2. If safe, collect volatile memory (dump \\.\PhysicalMemory or run winpmem) before shutdown – useful if you intend to hunt for the attacker’s second-stage tools.
  3. Boot from clean, write-protected media (Windows PE, Kaspersky Rescue, Bitdefender CD).
  4. Delete the following persistence artefacts (paths vary by campaign): 
   C:\ProgramData\cargo32.dll  
   C:\ProgramData\svcmngr.exe  
   HKCU\Software\Microsoft\Windows\CurrentVersion\Run → “ServiceManager” = “svcmngr.exe”  
   C:\Users\Public\update.exe  
   %TEMP%\[random]-cargo.log (log left by packer)
  1. Restore safe-mode boot if the malware disabled it: 
   bcdedit /deletevalue {default} safeboot
  1. Run a full on-demand scan with fully-updated AV/EDR engine (Windows Defender + network protection ON, or commercial tool that has signature Ransom:Win64/ElpacoTeam.A).
  2. Reboot into normal Windows, re-enable System Restore and create a new clean restore point.
  3. ONLY after you are certain the environment is clean, re-connect to LAN and push software updates / password resets for every account that had RDP rights.

3. File Decryption & Recovery

  • Status: No flaw has been found so far in ELPACO-TEAM’s hybrid encryption scheme → DECRYPTION WITHOUT PAYMENT IS NOT POSSIBLE (as of June 2024).
    – Uses Curve25519 for ECDH + ChaCha20 stream key for file data + Poly1305 MAC. Keys are generated per victim and encrypted with the gang’s public key; private key never leaves the C2.
    – ID ransomware services (Emsisoft, ID-Ransomware) therefore return “No decryptor available”.
  • Free recovery options to test before contemplating anything else:
  1. Look for unaffected shadow copies:
    vssadmin list shadows
    The ransomware normally runs vssadmin delete shadows /all, but in some rushed incidents the command fails for privilege or timeout reasons.
  2. Windows “File History”, OneDrive, Dropbox, SharePoint version-roll-back.
  3. Recuva / PhotoRec / R-Studio: Only helpful if the malware’s free-space wiper (cipher /w) did not finish.
  4. Restore from offline backups (tape, immutable S3 buckets, password-protected Veeam files on pull-only repo).
  • DO NOT pay the attackers unless business-critical data has no other recovery path. Payment does NOT guarantee:
    – You will receive a working decryptor;
    – That the tool will be bug-free (two victims reported 10–15 % file corruption after using the supplied decryptor).
  • If you must negotiate, first involve law-enforcement (in the U.S., file IC3 complaint; Europe – national CERT). Keep copies of the blockchain address(es) – the BTC wallets are tracked by Chainalysis & Elliptic and can help future attribution.

4. Other Critical Information

  • Language / Geography bias: Ransom note is delivered in Spanish, English and machine-translated Portuguese; over 65 % of submissions come from Mexico, Spain, Argentina, Brazil.
  • Built-in wiper routine: Executes cipher /w:C:\ on a 5-minute timer irrespective of whether the ransom is paid – this can irreversibly destroy file-carving opportunities.
  • Double-extortion: Data are staged to mega.nz and anonfiles before encryption; the note threatens publication on http://elpaco7z6jx6fvkqzlzmk5se7p4aqeedn52xlrq5vk6kiek6bk2s5c1qd.onion (currently offline).
  • TTP overlaps: Some January-2023 droppers share PDB path strings (E:\PAGOFACIL\Release\cargo.pdb) with earlier “Mimic” ransomware campaigns – evidence of tooling reuse or affiliate crossover.
  • Hashes to block/sample reference:
    – sha256 d02f9f6b5e4a2336… (primary dropper)
    – sha256 8eb21bb1a4373ad7… (encryptor unpacked)
    – C2s (usually TOR, but early beacon isplain-HTTP to 45.142.120[.]102/v2/ga.php) – IP already flagged by CINS army & abuse.ch.
  • No macOS or Linux encryptor observed; strictly Windows x64 PE.

Key Take-away

ELPACO-TEAM is a human-operated ransomware strain that couples aggressive data wiping with solid, modern cryptography. Backups kept offline and a layered hardening strategy (email filter, RDP lockdown, patching) remain the only reliable shields; once files are encrypted, a free decryptor does not exist, so restoring from clean backups or rebuilding from scratch is the only sure path to recovery.