aws_multi_factor_authentication_disabled.yml

name: AWS Multi-Factor Authentication Disabled
id: 374832b1-3603-420c-b456-b373e24d34c0
version: 1
date: '2022-10-04'
author: Bhavin Patel, Splunk
status: production
type: TTP
description: The following analytic identifies an attempt to disable multi-factor
  authentication for an AWS IAM user. An adversary who has obtained access to an AWS
  tenant may disable multi-factor authentication as a way to plant a backdoor and
  maintain persistence using a valid account. This way the attackers can keep persistance
  in the environment without adding new users.
data_source: []
search: '`cloudtrail` (eventName= DeleteVirtualMFADevice OR eventName=DeactivateMFADevice)
  | stats count min(_time) as firstTime max(_time) as lastTime by src eventName eventSource
  aws_account_id userAgent eventID awsRegion user_name userIdentity.arn status | `security_content_ctime(firstTime)`
  | `security_content_ctime(lastTime)` | `aws_multi_factor_authentication_disabled_filter`'
how_to_implement: The Splunk AWS Add-on is required to utilize this data. The search
  requires AWS Cloudtrail logs.
known_false_positives: AWS Administrators may disable MFA but it is highly unlikely
  for this event to occur without prior notice to the company
references:
- https://attack.mitre.org/techniques/T1621/
- https://aws.amazon.com/what-is/mfa/
tags:
  analytic_story:
  - AWS Identity and Access Management Account Takeover
  asset_type: AWS Account
  confidence: 80
  impact: 80
  message: User $user_name$ has disabled Multi-Factor authentication for AWS account
    $aws_account_id$
  mitre_attack_id:
  - T1586
  - T1586.003
  - T1621
  - T1556
  - T1556.006
  observable:
  - name: aws_account_id
    type: Other
    role:
    - Victim
  - name: user_name
    type: User
    role:
    - Victim
  - name: src
    type: IP Address
    role:
    - Attacker
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - src
  - eventName
  - eventSource
  - aws_account_id
  - errorCode
  - errorMessage
  - userAgent
  - eventID
  - awsRegion
  - user_name
  - userIdentity.arn
  risk_score: 64
  security_domain: threat
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1621/aws_mfa_disabled/cloudtrail.json
    sourcetype: aws:cloudtrail
    source: aws_cloudtrail
    update_timestamp: true