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

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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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