Suspicious New Root Certificate Authority Added (via auditlogs)

This rule detects newly added root certificate authority to an AzureAD tenant to support certificate based authentication.

SigmamediumCloudv1
sigma
title: Suspicious New Root Certificate Authority Added (via auditlogs)
id: 9877d03c-0e72-5369-b636-897f66a7cbd0
status: stable
description: This rule detects newly added root certificate authority to an AzureAD tenant to support certificate based authentication.
references:
    - https://attack.mitre.org/techniques/T1556/
    - https://posts.specterops.io/passwordless-persistence-and-privilege-escalation-in-azure-98a01310be3f
    - https://goodworkaround.com/2022/02/15/digging-into-azure-ad-certificate-based-authentication/
author: Huntrule Team
date: 2026-03-25
tags:
    - attack.credential-access
    - attack.persistence
    - attack.privilege-escalation
    - attack.defense-impairment
    - attack.t1556
logsource:
    product: azure
    service: auditlogs
detection:
    selection:
        OperationName: 'Set Company Information'
        TargetResources.modifiedProperties.newValue|contains: 'TrustedCAsForPasswordlessAuth'
    condition: selection
falsepositives:
    - Unknown
level: medium

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.