aws_cloudtrail_createnetworkaclentry.yml

name: AWS CloudTrail CreateNetworkAclEntry
id: 45934028-10ec-4ab5-a7b1-a6349b833e67
version: 2
date: '2025-01-23'
author: Patrick Bareiss, Splunk
description: Logs the creation of new entries in a network ACL, including rules to
  allow or deny specific network traffic.
mitre_components:
- Firewall Rule Modification
- Network Connection Creation
- Cloud Service Modification
- Cloud Service Metadata
source: aws_cloudtrail
sourcetype: aws:cloudtrail
separator: eventName
separator_value: CreateNetworkAclEntry
supported_TA:
- name: Splunk Add-on for AWS
  url: https://splunkbase.splunk.com/app/1876
  version: 7.9.1
fields:
- _time
- action
- app
- awsRegion
- aws_account_id
- change_type
- command
- date_hour
- date_mday
- date_minute
- date_month
- date_second
- date_wday
- date_year
- date_zone
- dest
- direction
- dvc
- errorCode
- eventCategory
- eventID
- eventName
- eventSource
- eventTime
- eventType
- eventVersion
- eventtype
- host
- index
- linecount
- managementEvent
- msg
- object
- object_category
- object_id
- product
- protocol
- protocol_code
- punct
- readOnly
- recipientAccountId
- region
- requestID
- requestParameters.aclProtocol
- requestParameters.cidrBlock
- requestParameters.egress
- requestParameters.networkAclId
- requestParameters.ruleAction
- requestParameters.ruleNumber
- responseElements._return
- responseElements.requestId
- rule_action
- signature
- source
- sourceIPAddress
- sourcetype
- splunk_server
- src
- src_ip
- src_ip_range
- start_time
- status
- tag
- tag::eventtype
- timeendpos
- timestartpos
- user
- userAgent
- userIdentity.accessKeyId
- userIdentity.accountId
- userIdentity.arn
- userIdentity.principalId
- userIdentity.sessionContext.attributes.creationDate
- userIdentity.sessionContext.attributes.mfaAuthenticated
- userIdentity.sessionContext.sessionIssuer.accountId
- userIdentity.sessionContext.sessionIssuer.arn
- userIdentity.sessionContext.sessionIssuer.principalId
- userIdentity.sessionContext.sessionIssuer.type
- userIdentity.sessionContext.sessionIssuer.userName
- userIdentity.type
- 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": "AssumedRole", "principalId":
  "AROAIJIESMXKGCJRCTPR6:pbareiss@splunk.local", "arn": "arn:aws:sts::111111111111:assumed-role/okta_adm_role/pbareiss@splunk.local",
  "accountId": "111111111111", "accessKeyId": "ASIAYTOGP2RLF3F7BXZK", "sessionContext":
  {"sessionIssuer": {"type": "Role", "principalId": "AROAIJIESMXKGCJRCTPR6", "arn":
  "arn:aws:iam::111111111111:role/okta_adm_role", "accountId": "111111111111", "userName":
  "okta_adm_role"}, "webIdFederationData": {}, "attributes": {"mfaAuthenticated":
  "false", "creationDate": "2021-01-12T08:36:15Z"}}}, "eventTime": "2021-01-12T08:38:39Z",
  "eventSource": "ec2.amazonaws.com", "eventName": "CreateNetworkAclEntry", "awsRegion":
  "eu-central-1", "sourceIPAddress": "95.90.199.65", "userAgent": "console.ec2.amazonaws.com",
  "requestParameters": {"networkAclId": "acl-078ccebebcbabe175", "ruleNumber": 10,
  "egress": false, "ruleAction": "allow", "icmpTypeCode": {}, "portRange": {}, "aclProtocol":
  "-1", "cidrBlock": "0.0.0.0/0"}, "responseElements": {"requestId": "d29c9c32-3a72-48d3-b612-6ba795e9ec64",
  "_return": true}, "requestID": "d29c9c32-3a72-48d3-b612-6ba795e9ec64", "eventID":
  "6d1ce00e-4099-463c-8a4d-2af2fb2178ba", "readOnly": false, "eventType": "AwsApiCall",
  "managementEvent": true, "eventCategory": "Management", "recipientAccountId": "111111111111"}'
output_fields:
- dest
- user
- user_agent
- src
- vendor_account
- vendor_region
- vendor_product