Query: Sigma rule for Monitor and alert on conditional access changes where non approved actor removed CA Policy.
Matching passage: Sigma rule: Monitor and alert on conditional access changes where non approved actor removed CA Policy.. Logsource: azure / auditlogs. Rule: title: CA Policy Removed by Non Approved Actor id: 26e7c5e2-6545-481e-b7e6-050143459635 status: test description: Monitor and alert on conditional access changes where non approved actor removed CA Policy. references: - https://learn.microsoft.com/en-us/entra/architecture/security-operations-infrastructure#conditional-access author: Corissa Koopmans, '@corissalea' date: 2022-07-19 tags: - attack.privilege-escalation - attack.credential-access - attack.persistence - attack.defense-impairment - attack.t1548 - attack.t1556 logsource: product: azure service: auditlogs detection: selection: properties.message: Delete conditional access policy condition: selection falsepositives: - Misconfigured role permissions - Verify whether the user identity, user agent, and/or hostname should be making changes in your environment. level: medium
Near-miss passage: Sigma rule: Detects successful deletion or disabling of an AWS GuardDuty detector, possibly by an attacker trying to avoid detection. Logsource: aws / cloudtrail. Rule: title: AWS GuardDuty Detector Deleted Or Updated id: d2656e78-c069-4571-8220-9e0ab5913f19 status: experimental description: 'Detects successful deletion or disabling of an AWS GuardDuty detector, possibly by an attacker trying to avoid detection of its malicious activities. Upon deletion, GuardDuty stops monitoring the environment and all existing findings are lost. Verify with the user identity that this activity is legitimate. ' references: - https://docs.aws.amazon.com/guardduty/latest/APIReference/API_DeleteDetector.html - https://docs.aws.amazon.com/guardduty/latest/APIReference/API_UpdateDetector.html - https://docs.aws.amazon.com/guardduty/latest/ug/guardduty_suspend-disable.html - https://docs.datadoghq.com/security/default_rules/719-39f-9cd/ - https://docs.prismacloud.io/en/enterprise-edition/policy-reference/aws-policies/aws-general-policies/ensure-aws-guardduty-detector-is-enabled - https://docs.stellarcyber.ai/5.2.x/Using/ML/Alert-Rule-Based-Potentially_Malicious_AWS_Activity.html - https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_GuardDutyDisabled.yaml - https://github.com/elastic/detection-rules/blob/main/rules/integrations/aws/defense_evasion_guardduty_detector_deletion.toml - https://help.fortinet.com/fsiem/Public_Resource_Access/7_4_0/rules/PH_RULE_AWS_GuardDuty_Detector_Deletion.htm - https://research.splunk.com/sources/5d8bd475-c8bc-4447-b27f-efa508728b90/ - https://suktech24.com/2025/07/17/aws-threat-detection-rule-guardduty-detector-disabled-or-suspended/ - https://www.atomicredteam.io/atomic-red-team/atomics/T156001#atomic-test-46---aws---guardduty-suspension-or-deletion author: suktech24 date: 2025-11-27 tags: - attack.defense-impairment - attack.t1685 - attack.t1685.002 logsource: product: aws service: cloudtrail detection: selection_event_source: eventSource: guardduty.amazonaws.com selection_action_delete: eventName: DeleteDetector selection_action_update: eventName: UpdateDetector requestParameters.enable: 'false' selection_status_success: errorCode: Success selection_status_null: errorCode: null condition: selection_event_source and 1 of selection_action_* and 1 of selection_status_* falsepositives: - Legitimate detector deletion by an admin (e.g., during account decommissioning). - Temporary disablement for troubleshooting (verify via change management tickets). - Automated deployment tools (e.g. Terraform) managing GuardDuty state. level: high