aws_cloudtrail_getobject.yml

name: AWS CloudTrail GetObject
id: 5063cb10-84c0-44af-ade4-ab9ecad11dfe
version: 2
date: '2025-01-23'
author: Patrick Bareiss, Splunk
description: Logs an event when a request is made to access an object stored in an
  AWS S3 bucket.
mitre_components:
- Cloud Storage Access
- Cloud Storage Metadata
- Cloud Storage Enumeration
source: aws_cloudtrail
sourcetype: aws:cloudtrail
separator: eventName
separator_value: GetObject
supported_TA:
- name: Splunk Add-on for AWS
  url: https://splunkbase.splunk.com/app/1876
  version: 7.9.1
fields:
- _time
- additionalEventData.AuthenticationMethod
- additionalEventData.CipherSuite
- additionalEventData.SignatureVersion
- additionalEventData.bytesTransferredIn
- additionalEventData.bytesTransferredOut
- additionalEventData.x-amz-id-2
- app
- awsRegion
- aws_account_id
- command
- date_hour
- date_mday
- date_minute
- date_month
- date_second
- date_wday
- date_year
- date_zone
- dest
- dvc
- errorCode
- eventCategory
- eventID
- eventName
- eventSource
- eventTime
- eventType
- eventVersion
- host
- index
- linecount
- managementEvent
- msg
- object_category
- product
- punct
- readOnly
- recipientAccountId
- region
- requestID
- requestParameters.Host
- requestParameters.bucketName
- requestParameters.key
- requestParameters.x-amz-request-payer
- resources{}.ARN
- resources{}.accountId
- resources{}.type
- responseElements
- signature
- source
- sourceIPAddress
- sourcetype
- splunk_server
- src
- src_ip
- start_time
- timeendpos
- timestartpos
- tlsDetails.cipherSuite
- tlsDetails.clientProvidedHostHeader
- tlsDetails.tlsVersion
- user
- userAgent
- userIdentity.accessKeyId
- userIdentity.accountId
- userIdentity.arn
- userIdentity.principalId
- userIdentity.type
- userIdentity.userName
- userName
- user_access_key
- user_agent
- user_arn
- user_group_id
- user_id
- user_name
- user_type
- vendor
- vendor_account
- vendor_product
- vendor_region
example_log: '{"eventVersion": "1.08", "userIdentity": {"type": "IAMUser", "principalId":
  "AIDAYTOGP2RLCNEAQXWZV", "arn": "arn:aws:iam::111111111111:user/console", "accountId":
  "111111111111", "accessKeyId": "AKIAYTOGP2RLF5EAXXXX", "userName": "console"}, "eventTime":
  "2023-04-11T01:18:47Z", "eventSource": "s3.amazonaws.com", "eventName": "GetObject",
  "awsRegion": "us-west-2", "sourceIPAddress": "12.26.0.38", "userAgent": "[aws-cli/2.11.2
  Python/3.11.2 Darwin/22.3.0 exe/x86_64 prompt/off command/s3.cp]", "requestParameters":
  {"bucketName": "security-content", "Host": "security-content.s3.us-west-2.amazonaws.com",
  "x-amz-request-payer": "requester", "key": "stories/windows_discovery_techniques.yml"},
  "responseElements": null, "additionalEventData": {"SignatureVersion": "SigV4", "CipherSuite":
  "ECDHE-RSA-AES128-GCM-SHA256", "bytesTransferredIn": 0, "AuthenticationMethod":
  "AuthHeader", "x-amz-id-2": "dcha0yrujT+O4FHsYxHx48KxMk4+wtO7MaNRwFOFs46R1PynKWcCsbLScYEFytN+Vt35hyq1cek=",
  "bytesTransferredOut": 1136}, "requestID": "GVSEBM08Z93FB3BT", "eventID": "2b7231c2-892d-464e-8880-1e4f81ae7eb2",
  "readOnly": true, "resources": [{"type": "AWS::S3::Object", "ARN": "arn:aws:s3:::security-content/stories/windows_discovery_techniques.yml"},
  {"accountId": "111111111111", "type": "AWS::S3::Bucket", "ARN": "arn:aws:s3:::security-content"}],
  "eventType": "AwsApiCall", "managementEvent": false, "recipientAccountId": "111111111111",
  "eventCategory": "Data", "tlsDetails": {"tlsVersion": "TLSv1.2", "cipherSuite":
  "ECDHE-RSA-AES128-GCM-SHA256", "clientProvidedHostHeader": "security-content.s3.us-west-2.amazonaws.com"}}'
output_fields:
- dest
- user
- user_agent
- src
- vendor_account
- vendor_region
- vendor_product