Sigma rule: MSSQL Server Failed Logon

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-88e814f8e906, updated 2024-06-26T00:00:00.000Z.

Rule

Title
MSSQL Server Failed Logon
Status
test
Level
low
Author
Nasreddine Bencherchali (Nextron Systems), j4son
Date
2023-10-11
Modified
2024-06-26
File
rules/windows/builtin/application/mssqlserver/win_mssql_failed_logon.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects failed logon attempts from clients to MSSQL server.

Log source

product
windows
service
application
definition
Requirements: Must enable MSSQL authentication.

Detection

selection:
    Provider_Name|contains: 'MSSQL' # Note: We use contains to account for other third party providers - See https://github.com/SigmaHQ/sigma/issues/4876
    EventID: 18456
condition: selection

False positives (as the rule lists them)

  • This event could stem from users changing an account's password that's used to authenticate via a job or an automated process. Investigate the source of such events and mitigate them

Tags

  • attack.credential-access
  • attack.t1110

MITRE ATT&CK ids this rule names

Related rules

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/builtin/application/mssqlserver/win_mssql_failed_logon.yml

Sources and licences

  • SigmaHQ

    "MSSQL Server Failed Logon" by Nasreddine Bencherchali (Nextron Systems), j4son (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/builtin/application/mssqlserver/win_mssql_failed_logon.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: MSSQL Server Failed Logon",
entity page, dataset version ref-88e814f8e906, updated 2024-06-26T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/218d2855-2bba-4f61-9c85-81d0ea63ac71 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 218d2855-2bba-4f61-9c85-81d0ea63ac71, 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.