typeanalysisfamilyanydesk-batch-dropperconfidencemediumscriptdropperpersistencec2defense-evasionlegitimate-remote-access-tool-abuse
SHA-256: 3f9176f2248abaeb0277a79ad534da2ef92dcb881024f5ef17b1e082dd262a6a

anydesk-batch-dropper: 3f9176f2 — Batch-script AnyDesk stager with SMTP exfil and task-scheduler persistence

Executive Summary

An 854-byte Windows batch script (pop.bat) that stages AnyDesk with a hardcoded unattended-access password, archives the victim's AnyDesk configuration, exfiltrates it via the blat SMTP client to a Dutch inbox, and establishes persistence via a logon-triggered scheduled task. All tooling is commodity or legitimate; the script itself is the payload. Static-only analysis (CAPE skipped ASCII text).

What It Is

  • SHA-256: 3f9176f2248abaeb0277a79ad534da2ef92dcb881024f5ef17b1e082dd262a6a
  • File type: ASCII text, DOS batch file, 854 bytes ^[file.txt]
  • Filename: pop.bat
  • CAPE: Skipped — unsupported binary class ^[dynamic-analysis.md]

Build / RE

Language / format: Plain DOS batch (cmd.exe interpreter). No packer, no obfuscation, no encoding. ^[file.txt]

Code quality: Extremely low — bare commands with hardcoded paths, credentials, and a typo in the task name (Auto apdate). ^[strings.txt:7] The script assumes a pre-populated staging directory (%userprofile%\Trust\mipo\) containing AnyDesk\AnyDesk.exe, driver.exe (WinRAR), blat.exe, AnyDesk.rar, and Trays\Trays.exe.

Anti-analysis: None. No debug checks, no VM detection. Relies on being a trivial text file that sandboxes may skip.

Embedded resources / staging: The script references external binaries it expects to already exist in the staging directory:

  • AnyDesk\AnyDesk.exe — legitimate AnyDesk client ^[strings.txt:4]
  • driver.exe — likely renamed WinRAR (a -r -ep -h are RAR archive switches) ^[strings.txt:5]
  • blat.exe — open-source Win32 SMTP client ^[strings.txt:6]
  • Trays\Trays.exe — unknown payload, launched as -tray masquerade ^[strings.txt:7]

Deploy / ATT&CK

Tactic Technique Evidence
Execution T1059.003 (Windows Command Shell) cmd.exe /c batch script. ^[file.txt]
Persistence T1053.005 (Scheduled Task/Job: Scheduled Task) schtasks /create /tn "Auto apdate" /tr ... /sc onlogon /rl highest ^[strings.txt:7]
Defense Evasion T1070.004 (Indicator Removal: File Deletion) del /q %userprofile%\Trust\mipo\*.{cmd,txt,rar,exe,pdf} ^[strings.txt:1,2,8,9,10]
Defense Evasion T1219 (Remote Access Software) Hardcodes AnyDesk unattended-access password QWERTY1234566. ^[strings.txt:4]
Collection T1560 (Archive Collected Data) WinRAR archives %ProgramData%\AnyDesk into AnyDesk.rar with password limpid2903392. ^[strings.txt:5]
Exfiltration T1048.003 (Exfiltration Over Unencrypted/Obfuscated Non-C2 Protocol) blat.exe SMTP to in@okbm-bus.nl via mail.versio.nl:587. ^[strings.txt:6]

C2 / Infrastructure:

  • Remote access: AnyDesk with hardcoded password QWERTY1234566 and unattended-access flag. ^[strings.txt:4]
  • Exfil: SMTP via mail.versio.nl (Dutch hosting provider, Versio/Hostnet) on port 587. Credentials: out@okbm-bus.nl / Kw52heHEBP5Rwe8D99CW. ^[strings.txt:6]
  • Recipient: in@okbm-bus.nl — domain with Dutch geographic association.

Attribution / Locale:

  • Dutch infrastructure indicators (versio.nl, okbm-bus.nl). ^[strings.txt:6]
  • Task name typo (apdate instead of update) suggests non-native English or careless typing. ^[strings.txt:7]

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