Sigma rule: Dynamic CSharp Compile Artefact

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-a94f9f885e08, updated 2023-02-17T00:00:00.000Z.

Rule

Title
Dynamic CSharp Compile Artefact
Status
test
Level
low
Author
frack113
Date
2022-01-09
Modified
2023-02-17
File
rules/windows/file/file_event/file_event_win_csharp_compile_artefact.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

When C# is compiled dynamically, a .cmdline file will be created as a part of the process.
Certain processes are not typically observed compiling C# code, but can do so without touching disk.
This can be used to unpack a payload for execution

Log source

product
windows
category
file_event

Detection

selection:
    TargetFilename|endswith: '.cmdline'
condition: selection

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.stealth
  • attack.t1027.004

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/file/file_event/file_event_win_csharp_compile_artefact.yml

Sources and licences

  • SigmaHQ

    "Dynamic CSharp Compile Artefact" by frack113 (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/file/file_event/file_event_win_csharp_compile_artefact.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Dynamic CSharp Compile Artefact",
entity page, dataset version ref-a94f9f885e08, updated 2023-02-17T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/e4a74e34-ecde-4aab-b2fb-9112dd01aed0 (accessed 2026-11-03).
Underlying source: SigmaHQ rule e4a74e34-ecde-4aab-b2fb-9112dd01aed0, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.