Logging AWS Private Certificate Authority API calls using AWS CloudTrail

AWS Private Certificate Authority is integrated with AWS CloudTrail, a service that provides a record of actions taken by a user, role, or an AWS service in AWS Private CA. CloudTrail captures API calls and signing operations for AWS Private CA as events. The calls captured include calls from the AWS Private CA console and code calls to the AWS Private CA API operations. If you create a trail, you can enable continuous delivery of CloudTrail events to an Amazon S3 bucket, including events for AWS Private CA. If you don't configure a trail, you can still view the most recent events in the CloudTrail console in Event history. Using the information collected by CloudTrail, you can determine the request that was made to AWS Private CA, the IP address from which the request was made, who made the request, when it was made, and additional details.

To learn more about CloudTrail, see the AWS CloudTrail User Guide.

AWS Private CA information in CloudTrail

CloudTrail is enabled on your AWS account when you create the account. When activity occurs in AWS Private CA, that activity is recorded in a CloudTrail event along with other AWS service events in Event history. You can view, search, and download recent events in your AWS account. For more information, see Viewing events with CloudTrail Event history.

For an ongoing record of events in your AWS account, including events for AWS Private CA, create a trail. A trail enables CloudTrail to deliver log files to an Amazon S3 bucket. By default, when you create a trail in the console, the trail applies to all AWS Regions. The trail logs events from all Regions in the AWS partition and delivers the log files to the Amazon S3 bucket that you specify. Additionally, you can configure other AWS services to further analyze and act upon the event data collected in CloudTrail logs. For more information, see the following:

All AWS Private CA actions are logged by CloudTrail and are documented in the AWS Private CA API reference. For example, calls to the ImportCACertificate, IssueCertificate and CreateAuditReport actions generate entries in the CloudTrail log files.

Every event or log entry contains information about who generated the request. The identity information helps you determine the following:

For more information, see the CloudTrail userIdentity element.

For information about how CloudTrail delivers events — including delivery timing, durability, and integration with other AWS services — see Getting and viewing your CloudTrail log files and the AWS CloudTrail Service Level Agreement.

AWS Private CA management events

AWS Private CA integrates with CloudTrail to record API actions made by a user, a role, or an AWS service in AWS Private CA. You can use CloudTrail to monitor AWS Private CA API requests in real time and store logs in Amazon Simple Storage Service, Amazon CloudWatch Logs, and Amazon CloudWatch Events. AWS Private CA supports logging the following actions and operations as events in CloudTrail log files:

Identifying the original requester

When an intermediate service calls IssueCertificate on behalf of end-users or workloads, the CloudTrail event records the intermediate service's IAM identity in the userIdentity field — not the original requester.

To trace certificate issuance back to the original requester, the intermediate service can propagate identity information using standard IAM mechanisms:

These identity attributes are recorded in CloudTrail events for all AWS service calls, including AWS Private CA API operations.

AWS Private CA service events

In addition to management events recorded from API calls, AWS Private CA generates service events that provide visibility into internal operations performed on your behalf. These events have an eventType of AwsServiceEvent and are logged automatically to your CloudTrail trail.

IssueCertificateDetails event

AWS Private CA generates an IssueCertificateDetails event when a certificate issuance attempt completes. The event records the outcome — whether the certificate was successfully issued or the issuance failed — and describes the certificate issuance process, including details such as:

When a certificate is issued from a shared CA, the event is delivered to both the CA owner's account and the requester's account. For failed issuance attempts, the event may include the statusReason field explaining the cause of failure.

Example: Successful certificate issuance

The following example shows an IssueCertificateDetails event for a successfully issued certificate.

{
    "eventVersion": "1.11",
    "userIdentity": {
        "accountId": "111122223333",
        "invokedBy": "acm-pca.amazonaws.com"
    },
    "eventTime": "2026-08-10T15:27:20Z",
    "eventSource": "acm-pca.amazonaws.com",
    "eventName": "IssueCertificateDetails",
    "awsRegion": "us-west-2",
    "sourceIPAddress": "acm-pca.amazonaws.com",
    "userAgent": "acm-pca.amazonaws.com",
    "requestParameters": null,
    "responseElements": null,
    "eventID": "83fecbfe-7e3a-4a14-8968-c99ad2d30d39",
    "readOnly": false,
    "resources": [
        {
            "accountId": "111122223333",
            "type": "AWS::ACMPCA::CertificateAuthority",
            "ARN": "arn:aws:acm-pca:us-west-2:111122223333:certificate-authority/9bb0e8f5-b024-4517-b0bb-e886cb34ac01"
        },
        {
            "accountId": "111122223333",
            "type": "AWS::ACMPCA::Certificate",
            "ARN": "arn:aws:acm-pca:us-west-2:111122223333:certificate-authority/9bb0e8f5-b024-4517-b0bb-e886cb34ac01/certificate/1a98eb0323009660dff81ac79ab4539e"
        }
    ],
    "eventType": "AwsServiceEvent",
    "managementEvent": true,
    "recipientAccountId": "111122223333",
    "serviceEventDetails": {
        "tbsCertificate": "MIIBZaADAgECAhAamOsDIwCWYN...",
        "issuerAuthorityKeyIdentifier": "16:E9:CC:B3:8A:DE:98:0F:10:BB:48:53:A4:1D:FD:A5:F2:EC:FE:5D",
        "issuerSerialNumber": "01",
        "issuerName": "CN=Example Intermediate CA",
        "subject": "CN=www.example.com",
        "serialNumber": "1A:98:EB:03:23:00:96:60:DF:F8:1A:C7:9A:B4:53:9E",
        "notBefore": "2026-08-10T14:27:20Z",
        "notAfter": "2026-08-17T15:27:20Z",
        "issuedAt": "2026-08-10T15:27:20Z",
        "templateArn": "arn:aws:acm-pca:::template/EndEntityCertificate/V1",
        "signingAlgorithm": "ECDSAWITHSHA256",
        "status": "ISSUED"
    },
    "eventCategory": "Management"
}

Example: Failed certificate issuance

The following example shows an IssueCertificateDetails event for a failed certificate issuance. When issuance fails, the status field is FAILED and the statusReason field describes the cause. The validity fields (notBefore, notAfter) and issuedAt are omitted because no certificate was issued. Fields derived from the TBS certificate (tbsCertificate, subject, issuerName, serialNumber, and issuerAuthorityKeyIdentifier) are present only when the failure occurred after AWS Private CA generated the TBS certificate.

{
    "eventVersion": "1.11",
    "userIdentity": {
        "accountId": "111122223333",
        "invokedBy": "acm-pca.amazonaws.com"
    },
    "eventTime": "2026-08-10T15:27:20Z",
    "eventSource": "acm-pca.amazonaws.com",
    "eventName": "IssueCertificateDetails",
    "awsRegion": "us-west-2",
    "sourceIPAddress": "acm-pca.amazonaws.com",
    "userAgent": "acm-pca.amazonaws.com",
    "requestParameters": null,
    "responseElements": null,
    "eventID": "fedcba98-7654-3210-fedc-ba9876543210",
    "readOnly": false,
    "resources": [
        {
            "accountId": "111122223333",
            "type": "AWS::ACMPCA::CertificateAuthority",
            "ARN": "arn:aws:acm-pca:us-west-2:111122223333:certificate-authority/9bb0e8f5-b024-4517-b0bb-e886cb34ac01"
        },
        {
            "accountId": "111122223333",
            "type": "AWS::ACMPCA::Certificate",
            "ARN": "arn:aws:acm-pca:us-west-2:111122223333:certificate-authority/9bb0e8f5-b024-4517-b0bb-e886cb34ac01/certificate/d6b81f1bf0563e97c29584a55c3ea553"
        }
    ],
    "eventType": "AwsServiceEvent",
    "managementEvent": true,
    "recipientAccountId": "111122223333",
    "serviceEventDetails": {
        "tbsCertificate": "MIIBZaADAgECAhAamOsDIwCWYN...",
        "issuerAuthorityKeyIdentifier": "16:E9:CC:B3:8A:DE:98:0F:10:BB:48:53:A4:1D:FD:A5:F2:EC:FE:5D",
        "issuerSerialNumber": "01",
        "issuerName": "CN=Example Intermediate CA",
        "subject": "CN=www.example.com",
        "serialNumber": "D6:B8:1F:1B:F0:56:3E:97:C2:95:84:A5:5C:3E:A5:53",
        "templateArn": "arn:aws:acm-pca:::template/EndEntityCertificate/V1",
        "signingAlgorithm": "ECDSAWITHSHA256",
        "status": "FAILED",
        "statusReason": "Name Constraints violation: DNS name not found in a permitted subtree."
    },
    "eventCategory": "Management"
}

The following table describes the fields in the serviceEventDetails object.

Example AWS Private CA events

A trail is a configuration that enables delivery of events as log files to an Amazon S3 bucket that you specify. CloudTrail log files contain one or more log entries. An event represents a single request from any source and includes information about the requested action, the date and time of the action, request parameters, and so on. CloudTrail log files aren't an ordered stack trace of the public API calls, so they don't appear in any specific order.

The following are examples of AWS Private CA CloudTrail events.

Example 1: Management event, IssueCertificate

The following example shows a CloudTrail log entry that demonstrates the IssueCertificate action.

{
   "version":"0",
   "id":"event_ID",
   "detail-type":"ACM Private CA Certificate Issuance",
   "source":"aws.acm-pca",
   "account":"account",
   "time":"2019-11-04T19:57:46Z",
   "region":"region",
   "resources":[
      "arn:aws:acm-pca:us-east-1:111122223333:certificate-authority/11223344-1234-1122-2233-112233445566",
      "arn:aws:acm-pca:region:account:certificate-authority/CA_ID/certificate/certificate_ID"
   ],
   "detail":{
      "result":"success"
   }
}

Example 2: Management event, ImportCertificateAuthorityCertificate

The following example shows a CloudTrail log entry that demonstrates the ImportCertificateAuthorityCertificate action.

{
   "eventVersion":"1.05",
   "userIdentity":{
      "type":"IAMUser",
      "principalId":"account",
      "arn":"arn:aws:iam::account:user/name",
      "accountId":"account",
      "accessKeyId":"key_ID"
   },
   "eventTime":"2018-01-26T21:53:28Z",
   "eventSource":"acm-pca.amazonaws.com",
   "eventName":"ImportCertificateAuthorityCertificate",
   "awsRegion":"region",
   "sourceIPAddress":"IP_address",
   "userAgent":"agent",
   "requestParameters":{
      "certificateAuthorityArn":"arn:aws:acm-pca:us-east-1:111122223333:certificate-authority/11223344-1234-1122-2233-112233445566",
      "certificate":{
         "hb":[
            45,
            45,
            ...10
         ],
         "offset":0,
         "isReadOnly":false,
         "bigEndian":true,
         "nativeByteOrder":false,
         "mark":-1,
         "position":1257,
         "limit":1257,
         "capacity":1257,
         "address":0
      },
      "certificateChain":{
         "hb":[
            45,
            45,
            ...10
         ],
         "offset":0,
         "isReadOnly":false,
         "bigEndian":true,
         "nativeByteOrder":false,
         "mark":-1,
         "position":1139,
         "limit":1139,
         "capacity":1139,
         "address":0
      }
   },
   "responseElements":null,
   "requestID":"request_ID",
   "eventID":"event_ID",
   "eventType":"AwsApiCall",
   "recipientAccountId":"account"
}