AWS Credential Access RDS Password reset

name: AWS Credential Access RDS Password reset
id: 6153c5ea-ed30-4878-81e6-21ecdb198189
version: 11
date: '2026-03-10'
author: Gowthamaraj Rajendran, Splunk
status: production
type: TTP
description: The following analytic detects the resetting of the master user password for an Amazon RDS DB instance. It leverages AWS CloudTrail logs to identify events where the `ModifyDBInstance` API call includes a new `masterUserPassword` parameter. This activity is significant because unauthorized password resets can grant attackers access to sensitive data stored in production databases, such as credit card information, PII, and healthcare data. If confirmed malicious, this could lead to data breaches, regulatory non-compliance, and significant reputational damage. Immediate investigation is required to determine the legitimacy of the password reset.
data_source:
    - AWS CloudTrail ModifyDBInstance
search: |-
    `cloudtrail` eventSource="rds.amazonaws.com" eventName=ModifyDBInstance "requestParameters.masterUserPassword"=*
      | rename user_name as user
      | stats count min(_time) as firstTime max(_time) as lastTime values(requestParameters.dBInstanceIdentifier) as database_id
        BY signature dest user
           user_agent src vendor_account
           vendor_region vendor_product
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `aws_credential_access_rds_password_reset_filter`
how_to_implement: You must install splunk AWS add on and Splunk App for AWS. This search works with AWS CloudTrail logs.
known_false_positives: Users may genuinely reset the RDS password.
references:
    - https://aws.amazon.com/premiumsupport/knowledge-center/reset-master-user-password-rds
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: $database_id$ password has been reset from IP $src$
    risk_objects:
        - field: database_id
          type: system
          score: 50
    threat_objects:
        - field: src
          type: ip_address
tags:
    analytic_story:
        - AWS Identity and Access Management Account Takeover
        - Scattered Lapsus$ Hunters
    asset_type: AWS Account
    mitre_attack_id:
        - T1110
        - T1586.003
    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/T1110.002/aws_rds_password_reset/aws_cloudtrail_events.json
          source: aws_cloudtrail
          sourcetype: aws:cloudtrail