AWS ECR Container Upload Outside Business Hours

name: AWS ECR Container Upload Outside Business Hours
id: d4c4d4eb-3994-41ca-a25e-a82d64e125bb
version: 10
date: '2026-03-10'
author: Patrick Bareiss, Splunk
status: production
type: Anomaly
description: The following analytic detects the upload of a new container image to AWS Elastic Container Registry (ECR) outside of standard business hours. It leverages AWS CloudTrail logs to identify `PutImage` events occurring between 8 PM and 8 AM or on weekends. This activity is significant because container uploads outside business hours can indicate unauthorized or suspicious activity, potentially pointing to a compromised account or insider threat. If confirmed malicious, this could allow an attacker to deploy unauthorized or malicious containers, leading to potential data breaches or service disruptions.
data_source:
    - AWS CloudTrail PutImage
search: |-
    `cloudtrail` eventSource=ecr.amazonaws.com eventName=PutImage date_hour>=20 OR date_hour<8 OR date_wday=saturday OR date_wday=sunday
      | rename requestParameters.* as *
      | rename repositoryName AS repository
      | rename user_name as user
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY signature user user_agent
           src vendor_account vendor_region
           vendor_product repository
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `aws_ecr_container_upload_outside_business_hours_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: When your development is spreaded in different time zones, applying this rule can be difficult.
references:
    - https://attack.mitre.org/techniques/T1204/003/
drilldown_searches:
    - name: View the detection results for - "$user$"
      search: '%original_detection_search% | search  user = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") starthoursago=168  | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
rba:
    message: Container uploaded outside business hours from $user$
    risk_objects:
        - field: user
          type: user
          score: 20
    threat_objects:
        - field: src
          type: ip_address
tags:
    analytic_story:
        - Dev Sec Ops
    asset_type: AWS Account
    mitre_attack_id:
        - T1204.003
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: network
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1204.003/aws_ecr_container_upload/aws_ecr_container_upload.json
          sourcetype: aws:cloudtrail
          source: aws_cloudtrail