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Description

The following query uses IAM events to track the success of a group being deleted on AWS. This is typically not indicative of malicious behavior, but a precurser to additional events thay may unfold. Review parallel IAM events - recently added users, new groups and so forth. Inversely, review failed attempts in a similar manner.

  • Type: Hunting
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud, Splunk Security Analytics for AWS
  • Datamodel:
  • Last Updated: 2021-03-31
  • Author: Michael Haag, Splunk
  • ID: e776d06c-9267-11eb-819b-acde48001122

ATT&CK

ID Technique Tactic
T1069.003 Cloud Groups Discovery
T1098 Account Manipulation Persistence
T1069 Permission Groups Discovery Discovery
`cloudtrail` eventSource=iam.amazonaws.com eventName=DeleteGroup errorCode=success (userAgent!=*.amazonaws.com) 
| stats count min(_time) as firstTime max(_time) as lastTime values(requestParameters.groupName) as group_deleted by src eventName eventSource errorCode user_agent awsRegion userIdentity.principalId user_arn 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `aws_iam_successful_group_deletion_filter`

Associated Analytic Story

How To Implement

The Splunk AWS Add-on and Splunk App for AWS is required to utilize this data. The search requires AWS Cloudtrail logs.

Required field

  • _time
  • eventName
  • userAgent
  • errorCode
  • requestParameters.groupName

Kill Chain Phase

  • Actions on Objectives

Known False Positives

This detection will require tuning to provide high fidelity detection capabilties. Tune based on src addresses (corporate offices, VPN terminations) or by groups of users. Not every user with AWS access should have permission to delete groups (least privilege).

RBA

Risk Score Impact Confidence Message
5.0 10 50 User $user_arn$ has sucessfully deleted mulitple groups $group_deleted$ from $src$

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

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