ASL AWS Defense Evasion Impair Security Services

name: ASL AWS Defense Evasion Impair Security Services
id: 5029b681-0462-47b7-82e7-f7e3d37f5a2d
version: 9
date: '2026-02-25'
author: Patrick Bareiss, Bhavin Patel, Gowthamaraj Rajendran, Splunk
status: production
type: Hunting
description: The following analytic detects the deletion of critical AWS Security Services configurations, such as CloudWatch alarms, GuardDuty detectors, and Web Application Firewall rules. It leverages Amazon Security Lake logs to identify specific API calls like "DeleteLogStream" and "DeleteDetector." This activity is significant because adversaries often use these actions to disable security monitoring and evade detection. If confirmed malicious, this could allow attackers to operate undetected, leading to potential data breaches, unauthorized access, and prolonged persistence within the AWS environment.
data_source:
    - ASL AWS CloudTrail
search: |-
    `amazon_security_lake` api.operation IN ("DeleteLogStream","DeleteDetector","DeleteIPSet","DeleteWebACL","DeleteRule","DeleteRuleGroup","DeleteLoggingConfiguration","DeleteAlarms")
      | fillnull
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY actor.user.uid api.operation api.service.name
           http_request.user_agent src_endpoint.ip actor.user.account.uid
           cloud.provider cloud.region
      | rename actor.user.uid as user api.operation as action api.service.name as dest http_request.user_agent as user_agent src_endpoint.ip as src actor.user.account.uid as vendor_account cloud.provider as vendor_product cloud.region as vendor_region
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `asl_aws_defense_evasion_impair_security_services_filter`
how_to_implement: The detection is based on Amazon Security Lake events from Amazon Web Services (AWS), which is a centralized data lake that provides security-related data from AWS services. To use this detection, you must ingest CloudTrail logs from Amazon Security Lake into Splunk. To run this search, ensure that you ingest events using the latest version of Splunk Add-on for Amazon Web Services (https://splunkbase.splunk.com/app/1876) or the Federated Analytics App.
known_false_positives: While this search has no known false positives, it is possible that it is a legitimate admin activity. Please consider filtering out these noisy events using userAgent, user_arn field names.
references:
    - https://docs.aws.amazon.com/cli/latest/reference/guardduty/index.html
    - https://docs.aws.amazon.com/cli/latest/reference/waf/index.html
    - https://www.elastic.co/guide/en/security/current/prebuilt-rules.html
tags:
    analytic_story:
        - AWS Defense Evasion
    asset_type: AWS Account
    mitre_attack_id:
        - T1562.008
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: threat
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1562.008/aws_delete_security_services/asl_ocsf_cloudtrail.json
          sourcetype: aws:asl
          source: aws_asl