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Description

This search looks for AWS CloudTrail events from AWS Elastic Container Service (ECR). A upload of a new container is normally done during business hours. When done outside business hours, we want to take a look into it.

  • Type: Anomaly
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud, Dev Sec Ops Analytics
  • Datamodel:
  • Last Updated: 2021-08-19
  • Author: Patrick Bareiss, Splunk
  • ID: d4c4d4eb-3994-41ca-a25e-a82d64e125bb

ATT&CK

ID Technique Tactic
T1204.003 Malicious Image Execution
T1204 User Execution Execution
`cloudtrail` eventSource=ecr.amazonaws.com eventName=PutImage date_hour>=20 OR date_hour<8 NOT (date_wday=saturday OR date_wday=sunday) 
| rename requestParameters.* as * 
| rename repositoryName AS image 
| eval phase="release" 
| eval severity="medium" 
| stats min(_time) as firstTime max(_time) as lastTime by awsRegion, eventName, eventSource, user, userName, src_ip, imageTag, registryId, image, phase, severity 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `aws_ecr_container_upload_outside_business_hours_filter`

Associated Analytic Story

How To Implement

You must install splunk AWS add on and Splunk App for AWS. This search works with AWS CloudTrail logs.

Required field

  • eventSource
  • eventName
  • awsRegion
  • requestParameters.imageTag
  • requestParameters.registryId
  • requestParameters.repositoryName
  • user
  • userName
  • src_ip

Kill Chain Phase

  • Actions on Objectives

Known False Positives

When your development is spreaded in different time zones, applying this rule can be difficult.

RBA

Risk Score Impact Confidence Message
49.0 70 70 Container uploaded outside business hours from $user$

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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