Query: rule covering Detects successful deletion or disabling of an AWS GuardDuty detector, possibly by an attacker trying to avoid detection
Matching 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
Near-miss passage: Sigma rule: Detects code fragments found in small and obfuscated AMSI bypass PowerShell scripts. Logsource: windows / ps_script. Rule: title: AMSI Bypass Pattern Assembly GetType id: e0d6c087-2d1c-47fd-8799-3904103c5a98 status: test description: Detects code fragments found in small and obfuscated AMSI bypass PowerShell scripts references: - https://www.mdsec.co.uk/2018/06/exploring-powershell-amsi-and-logging-evasion/ - https://twitter.com/cyb3rops/status/1588574518057979905?s=20&t=A7hh93ONM7ni1Rj1jO5OaA author: Florian Roth (Nextron Systems) date: 2022-11-09 tags: - attack.defense-impairment - attack.t1685 - attack.execution logsource: product: windows category: ps_script definition: 'Requirements: Script Block Logging must be enabled' detection: selection: ScriptBlockText|contains|all: - '[Ref].Assembly.GetType' - SetValue($null,$true) - NonPublic,Static condition: selection falsepositives: - Unknown level: high