Rules Contributing to Suspicious Microsoft Entra Sign-in Activity Alert

The following rules are used to identify suspicious Microsoft Entra sign-in activity. Any one or more of these will trigger the Microsoft Entra Suspicious Sign-in Activity Alert. Details for each rule can be viewed by clicking the More Details link in the description.

Title

Description

Use of Legacy Authentication Protocols

Alert on when legecy authentication has been used on an account

Rule ID

azure_9

Query

{'selection': {'login_result': 'success', 'ClientApp': ['Other clients', 'IMAP', 'POP3', 'MAPI', 'SMTP', 'Exchange ActiveSync', 'Exchange Web Services']}, 'filter': {'srcip_username': ''}, 'condition': 'selection and not filter'}

Log Source

Stellar Cyber Microsoft Entra Events configured.

Rule Source

SigmaHQ,60f6535a-760f-42a9-be3f-c9a0a025906e

Author: Yochana Henderson, '@Yochana-H'

Tactics, Techniques, and Procedures

CREDENTIAL_ACCESS, INITIAL_ACCESS, T1078.004, T1110

References

N/A

Severity

75

Suppression Logic Based On

  • srcip_username
  • stellar.rule_id

Additional Information

Maturity Creation Date Risk Level False Positives
experimental 2022/06/17 high

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

Suspicious SignIns From A Non Registered Device

Detects risky authencaition from a non AD registered device without MFA being required.

Rule ID

azure_10

Query

{'selection': {'ResultType': 0, 'RiskState': 'atRisk', 'DeviceDetail_trusttype': ''}, 'condition': 'selection'}

Log Source

Stellar Cyber Microsoft Entra Events configured.

Rule Source

SigmaHQ,572b12d4-9062-11ed-a1eb-0242ac120002

Author: Harjot Singh, '@cyb3rjy0t'

Tactics, Techniques, and Procedures

INITIAL_ACCESS, T1078

References

N/A

Severity

75

Suppression Logic Based On

  • srcip_username
  • stellar.rule_id

Additional Information

Maturity Creation Date Risk Level False Positives
experimental 2023/01/10 high

  • Unknown

Device Registration or Join Without MFA

Monitor and alert for device registration or join events where MFA was not performed.

Rule ID

azure_11

Query

{'selection': {'ResourceDisplayName': 'Device Registration Service', 'conditionalAccessStatus': 'success'}, 'filter_mfa': {'status_additionalDetails|startswith': 'MFA'}, 'condition': 'selection and not filter_mfa'}

Log Source

Stellar Cyber Microsoft Entra Events configured.

Rule Source

SigmaHQ,5afa454e-030c-4ab4-9253-a90aa7fcc581

Author: Michael Epping, '@mepples21'

Tactics, Techniques, and Procedures

INITIAL_ACCESS, T1078.004

References

N/A

Severity

50

Suppression Logic Based On

  • srcip_username
  • stellar.rule_id

Additional Information

Maturity Creation Date Risk Level False Positives
experimental 2022/06/28 medium

  • Unknown

Azure Unusual Authentication Interruption

Detects when there is an interruption in the authentication process.

Rule ID

azure_12

Query

{'selection_50097': {'ResultType': 50097}, 'selection_50155': {'ResultType': 50155}, 'selection_50158': {'ResultType': 50158}, 'condition': '1 of selection_*'}

Log Source

Stellar Cyber Microsoft Entra Events configured.

Rule Source

SigmaHQ,8366030e-7216-476b-9927-271d79f13cf3

Author: Austin Songer @austinsonger

Tactics, Techniques, and Procedures

INITIAL_ACCESS, T1078

References

N/A

Severity

50

Suppression Logic Based On

  • srcip_username
  • stellar.rule_id

Additional Information

Maturity Creation Date Risk Level False Positives
experimental 2021/11/26 medium

  • Unknown

Login to Disabled Account

Detect failed attempts to sign in to disabled accounts.

Rule ID

azure_14

Query

{'selection': {'ResultType': 50057}, 'condition': 'selection'}

Log Source

Stellar Cyber Microsoft Entra Events configured.

Rule Source

SigmaHQ,908655e0-25cf-4ae1-b775-1c8ce9cf43d8

Author: AlertIQ

Tactics, Techniques, and Procedures

INITIAL_ACCESS, T1078.004

References

N/A

Severity

50

Suppression Logic Based On

  • srcip_username
  • stellar.rule_id

Additional Information

Maturity Creation Date Risk Level False Positives
test 2021/10/10 medium

  • Unknown