:warning: THIS IS A EXPERIMENTAL DETECTION

This detection has been marked experimental by the Splunk Threat Research team. This means we have not been able to test, simulate, or build datasets for this detection. Use at your own risk. This analytic is NOT supported.

Try in Splunk Security Cloud

Description

This analytic identifies AWS DeleteTrail events within CloudTrail logs. Adversaries often try to impair their target's defenses by stopping their malicious activity from being logged, so that they may operate with stealth and avoid detection. When the adversary has the right type of permissions in the compromised AWS environment, they may delete the the entire cloudtrail that is logging activities in the environment.

  • Type: TTP

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2023-05-31
  • Author: Patrick Bareiss, Splunk
  • ID: 1f0b47e5-0134-43eb-851c-e3258638945e

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1562.008 Disable or Modify Cloud Logs Defense Evasion
T1562 Impair Defenses Defense Evasion
Kill Chain Phase
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


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`amazon_security_lake` api.operation=DeleteTrail 
| stats count min(_time) as firstTime max(_time) as lastTime by identity.user.account_uid identity.user.credential_uid identity.user.name identity.user.type identity.user.uid identity.user.uuid http_request.user_agent src_endpoint.ip cloud.region 
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `asl_aws_defense_evasion_delete_cloudtrail_filter`

Macros

The SPL above uses the following Macros:

:information_source: asl_aws_defense_evasion_delete_cloudtrail_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • api.service.name
  • api.operation
  • identity.user.account_uid
  • identity.user.credential_uid
  • identity.user.name
  • identity.user.type
  • identity.user.uid
  • identity.user.uuid
  • http_request.user_agent
  • src_endpoint.ip

How To Implement

You must install Splunk Add-On for AWS Version v7.0.0 (https://splunkbase.splunk.com/app/1876) that includes includes a merge of all the capabilities of the Splunk Add-on for Amazon Security Lake. This search works with Amazon Security Lake logs which are parsed in the Open Cybersecurity Schema Framework (OCSF)format.

Known False Positives

While this search has no known false positives, it is possible that an AWS admin has stopped cloudTrail logging. Please investigate this activity.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
90.0 100 90 User $identity.user.name$ has delete a CloudTrail logging for account id $identity.user.account_uid$

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

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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