Sigma rule: User Has Been Deleted Via Userdel

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-250f537d18ba, updated 2022-12-26T00:00:00.000Z.

Rule

Title: User Has Been Deleted Via Userdel
Status: test
Level: medium
Author: Tuan Le (NCSGroup)
Date: 2022-12-26
File: rules/linux/process_creation/proc_creation_lnx_userdel.yml
Commit: ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects execution of the "userdel" binary. Which is used to delete a user account and related files. This is sometimes abused by threat actors in order to cover their tracks

Log source

product: linux
category: process_creation

Detection

selection:
    Image|endswith: '/userdel'
condition: selection

False positives (as the rule lists them)

Legitimate administrator activities

MITRE ATT&CK ids this rule names

T1531

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/linux/process_creation/proc_creation_lnx_userdel.yml

Sources and licences

SigmaHQ
"User Has Been Deleted Via Userdel" by Tuan Le (NCSGroup) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/linux/process_creation/proc_creation_lnx_userdel.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: User Has Been Deleted Via Userdel",
entity page, dataset version ref-250f537d18ba, updated 2022-12-26T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/08f26069-6f80-474b-8d1f-d971c6fedea0 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 08f26069-6f80-474b-8d1f-d971c6fedea0, 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.