Windows Suspicious App and LOLBIN Dropping Executable Files to Disk

Alerts on Windows processes like Office/LOLBINs writing .exe/.dll and other executable-equivalent files to disk.

FreeReviewedSigma · High · v2

Product: windows
Category: file_event
Author: frack113, Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2022-08-21
Updated: 2026-07-31

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1218System Binary Proxy Execution
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags file creation events where a specific set of legitimate Windows applications and LOLBINs write executable or executable-equivalent artifacts to disk. Attackers commonly use trusted binaries to stage payloads, deliver malware, or write dropper outputs under a seemingly normal process name. It relies on Windows file event telemetry that includes the process image path and the target filename of created files.

Reporting behind it

Related detections9 linkedT1218 — drag to rearrange

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Malicious certutil Decodehex Payload Reconstruction by DarkGate

Malicious MSIX Package Execution via App Installer ms-appinstaller Protocol (via process_creation)

Malicious ViPNet Backdoor Loader via lumpdiag.exe Path Substitution

Suspicious BitLockerToGo Execution from Unusual Parent

Suspicious Proxy Execution via pcalua

Windows Suspicious App and LOLBIN Dropping Executable Files to Disk

Pivot detection · T1218 · 9 related

Changelog

v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

windows-suspicious-executable-dropping-by-known-apps-and-lolbins-f0540f7e

title: Windows Suspicious App and LOLBIN Dropping Executable Files to Disk
id: 820c32fc-87b2-4905-8da0-4bbc42091757
status: test
description: This rule flags file creation events where a specific set of legitimate Windows applications and LOLBINs write executable or executable-equivalent artifacts to disk. Attackers commonly use trusted binaries to stage payloads, deliver malware, or write dropper outputs under a seemingly normal process name. It relies on Windows file event telemetry that includes the process image path and the target filename of created files.
references:
  - https://github.com/Neo23x0/sysmon-config/blob/3f808d9c022c507aae21a9346afba4a59dd533b9/sysmonconfig-export-block.xml#L1326
  - https://dmpdump.github.io/posts/TelegramRat/
  - https://www.virustotal.com/gui/file/a0d5b30578acd1df9139e7a8a4bfc659dc2cf48f4dc0c5804b70890adeb9fa21/behavior
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/file/file_event/file_event_win_susp_legitimate_app_dropping_exe.yml
author: frack113, Florian Roth (Nextron Systems), Huntrule Team
date: 2022-08-21
modified: 2026-05-11
tags:
  - attack.stealth
  - attack.t1218
logsource:
  product: windows
  category: file_event
detection:
  selection:
    Image|endswith:
      - \eqnedt32.exe
      - \wordpad.exe
      - \wordview.exe
      - \certutil.exe
      - \certoc.exe
      - \CertReq.exe
      - \Desktopimgdownldr.exe
      - \esentutl.exe
      - \mshta.exe
      - \AcroRd32.exe
      - \RdrCEF.exe
      - \hh.exe
      - \finger.exe
    TargetFilename|endswith:
      - .com
      - .dll
      - .exe
      - .jar
      - .ocx
      - .pyc
  condition: selection
falsepositives:
  - Unknown
level: high
regression_tests_path: regression_data/rules/windows/file/file_event/file_event_win_susp_legitimate_app_dropping_exe/info.yml
license: DRL-1.1
related:
  - id: f0540f7e-2db3-4432-b9e0-3965486744bc
    type: derived

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