Sigma rule: Use of Legacy Authentication Protocols

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-d9dde1c21dfb, updated 2022-06-17T00:00:00.000Z.

Rule

Title
Use of Legacy Authentication Protocols
Status
test
Level
high
Author
Yochana Henderson, '@Yochana-H'
Date
2022-06-17
File
rules/cloud/azure/signin_logs/azure_legacy_authentication_protocols.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Alert on when legacy authentication has been used on an account

Log source

product
azure
service
signinlogs

Detection

selection:
    ActivityDetails: Sign-ins
    ClientApp:
        - Other client
        - IMAP
        - POP3
        - MAPI
        - SMTP
        - Exchange ActiveSync
        - Exchange Web Services
    Username: 'UPN'
condition: selection

False positives (as the rule lists them)

  • User has been put in acception group so they can use legacy authentication

Tags

  • attack.privilege-escalation
  • attack.persistence
  • attack.initial-access
  • attack.credential-access
  • attack.stealth
  • attack.t1078.004
  • 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/rules/cloud/azure/signin_logs/azure_legacy_authentication_protocols.yml

Sources and licences

  • SigmaHQ

    "Use of Legacy Authentication Protocols" by Yochana Henderson, '@Yochana-H' (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/cloud/azure/signin_logs/azure_legacy_authentication_protocols.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: Use of Legacy Authentication Protocols",
entity page, dataset version ref-d9dde1c21dfb, updated 2022-06-17T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/60f6535a-760f-42a9-be3f-c9a0a025906e (accessed 2026-11-03).
Underlying source: SigmaHQ rule 60f6535a-760f-42a9-be3f-c9a0a025906e, 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.