AWS Defense Evasion Update Cloudtrail

name: AWS Defense Evasion Update Cloudtrail
id: 7c921d28-ef48-4f1b-85b3-0af8af7697db
version: 9
date: '2026-03-10'
author: Gowthamaraj Rajendran, Splunk
status: production
type: TTP
description: The following analytic detects `UpdateTrail` events in AWS CloudTrail logs. It identifies attempts to modify CloudTrail settings, potentially to evade logging. The detection leverages CloudTrail logs, focusing on `UpdateTrail` events where the user agent is not the AWS console and the operation is successful. This activity is significant because altering CloudTrail settings can disable or limit logging, hindering visibility into AWS account activities. If confirmed malicious, this could allow attackers to operate undetected, compromising the integrity and security of the AWS environment.
data_source:
    - AWS CloudTrail UpdateTrail
search: |-
    `cloudtrail` eventName = UpdateTrail eventSource = cloudtrail.amazonaws.com userAgent !=console.amazonaws.com errorCode = success
      | rename user_name as user
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY signature dest user
           user_agent src vendor_account
           vendor_region vendor_product
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `aws_defense_evasion_update_cloudtrail_filter`
how_to_implement: You must install Splunk AWS Add on and enable CloudTrail logs in your AWS Environment.
known_false_positives: While this search has no known false positives, it is possible that an AWS admin has updated cloudtrail logging. Please investigate this activity.
references:
    - https://attack.mitre.org/techniques/T1562/008/
drilldown_searches:
    - name: View the detection results for - "$user$"
      search: '%original_detection_search% | search  user = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") starthoursago=168  | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
rba:
    message: User $user$ has updated a cloudtrail logging for account id $vendor_account$ from IP $src$
    risk_objects:
        - field: user
          type: user
          score: 50
    threat_objects:
        - field: src
          type: ip_address
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/update_cloudtrail/aws_cloudtrail_events.json
          source: aws_cloudtrail
          sourcetype: aws:cloudtrail