AWS CreateAccessKey

Name:AWS CreateAccessKey
id:2a9b80d3-6340-4345-11ad-212bf3d0d111
version:5
date:2024-10-17
author:Bhavin Patel, Splunk
status:production
type:Hunting
Description:The following analytic identifies the creation of AWS IAM access keys by a user for another user, which can indicate privilege escalation. It leverages AWS CloudTrail logs to detect instances where the user creating the access key is different from the user for whom the key is created. This activity is significant because unauthorized access key creation can allow attackers to establish persistence or exfiltrate data via AWS APIs. If confirmed malicious, this could lead to unauthorized access to AWS services, data exfiltration, and long-term persistence in the environment.
Data_source:

• -AWS CloudTrail CreateAccessKey

search:`cloudtrail` eventName = CreateAccessKey userAgent !=console.amazonaws.com errorCode = success
| eval match=if(match(userIdentity.userName,requestParameters.userName),1,0)
| search match=0
| stats count min(_time) as firstTime max(_time) as lastTime by requestParameters.userName src eventName eventSource aws_account_id errorCode userAgent eventID awsRegion userIdentity.principalId user_arn
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)` |`aws_createaccesskey_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:While this search has no known false positives, it is possible that an AWS admin has legitimately created keys for another user.
References:
  -https://bishopfox.com/blog/privilege-escalation-in-aws
  -https://rhinosecuritylabs.com/aws/aws-privilege-escalation-methods-mitigation-part-2/
drilldown_searches:
  :
tags:
  analytic_story:
    - 'AWS IAM Privilege Escalation'
  asset_type:AWS Account
  confidence:90
  impact:70
  message:User $user_arn$ is attempting to create access keys for $requestParameters.userName$ from this IP $src$
  mitre_attack_id:
    - 'T1136.003'
    - 'T1136'
  observable:
    name:'src'
    type:'IP Address'
    - role:
      - 'Attacker'
    name:'user_arn'
    type:'User'
    - role:
      - 'Attacker'
  product:
    - 'Splunk Enterprise'
    - 'Splunk Enterprise Security'
    - 'Splunk Cloud'
  required_fields:
    - '_time'
    - 'eventName'
    - 'userAgent'
    - 'errorCode'
    - 'requestParameters.userName'
  risk_score:63
  security_domain:network

tests:
 name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1078/aws_createaccesskey/aws_cloudtrail_events.json
  sourcetype: aws:cloudtrail
  source: aws_cloudtrail
  update_timestamp: True
manual_test:None