Sigma rule: Failed Logins with Different Accounts from Single Source - Linux

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-606e6e8d5847, updated 2023-03-24T00:00:00.000Z.

Rule

Title
Failed Logins with Different Accounts from Single Source - Linux
Status
unsupported
Level
medium
Author
Florian Roth (Nextron Systems)
Date
2017/02/16
Modified
2023/03/24
File
unsupported/linux/lnx_auth_susp_failed_logons_single_source.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects suspicious failed logins with different user accounts from a single source system

Log source

product
linux
service
auth

Detection

selection:
    pam_message: authentication failure
    pam_user: '*'
    pam_rhost: '*'
timeframe: 24h
condition: selection | count(pam_user) by pam_rhost > 3

False positives (as the rule lists them)

  • Terminal servers
  • Jump servers
  • Workstations with frequently changing users

Tags

  • attack.credential_access
  • attack.t1110

MITRE ATT&CK ids this rule names

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/unsupported/linux/lnx_auth_susp_failed_logons_single_source.yml

Sources and licences

  • SigmaHQ

    "Failed Logins with Different Accounts from Single Source - Linux" by Florian Roth (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/unsupported/linux/lnx_auth_susp_failed_logons_single_source.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: Failed Logins with Different Accounts from Single Source - Linux",
entity page, dataset version ref-606e6e8d5847, updated 2023-03-24T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/fc947f8e-ea81-4b14-9a7b-13f888f94e18 (accessed 2026-11-03).
Underlying source: SigmaHQ rule fc947f8e-ea81-4b14-9a7b-13f888f94e18, 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.