Sigma rule: Sign-in Failure Bad Password Threshold

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-d24cabfc0fd8, updated 2023-03-24T00:00:00.000Z.

Rule

Title
Sign-in Failure Bad Password Threshold
Status
unsupported
Level
high
Author
Corissa Koopmans, '@corissalea'
Date
2022/04/21
Modified
2023/03/24
File
unsupported/cloud/azure_aad_secops_signin_failure_bad_password_threshold.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Define a baseline threshold and then monitor and adjust to suit your organizational behaviors and limit false alerts from being generated.

Log source

product
azure
service
signinlogs

Detection

selection:
    ResultType: 50126
    ResultDescription: Invalid username or password or Invalid on-premises username or password.
filter_computer:
    TargetUserName|endswith: '$'
condition: selection and not filter_computer | count(TargetUserName) by IpAddress > 10

False positives (as the rule lists them)

  • Failed Azure AD Connect Synchronization
  • Service account use with an incorrect password specified
  • Misconfigured systems
  • Vulnerability scanners

Tags

  • attack.credential_access
  • attack.t1110

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/unsupported/cloud/azure_aad_secops_signin_failure_bad_password_threshold.yml

Sources and licences

  • SigmaHQ

    "Sign-in Failure Bad Password Threshold" by Corissa Koopmans, '@corissalea' (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/unsupported/cloud/azure_aad_secops_signin_failure_bad_password_threshold.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: Sign-in Failure Bad Password Threshold",
entity page, dataset version ref-d24cabfc0fd8, updated 2023-03-24T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/dff74231-dbed-42ab-ba49-83289be2ac3a (accessed 2026-11-03).
Underlying source: SigmaHQ rule dff74231-dbed-42ab-ba49-83289be2ac3a, 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.