How to obtain the credential (Access key ID) of the user who sent the message in the log of sent a message SMS.

Rephrasing the question:

Right now I'm sending SMS messages using SNS, but without using topics, i.e. directly to the destination phone number.

I have SNS set up to log delivery status of SMS messages to cloudwatch.

Problem:

However, the object received in the logs does not include the credential (access key) , is there a way to do so ?

I need it:

I need to know which IAM user credential (access key) was used to have access to send the message SMS via aws-sdk.

Whereas that:

1. AWSService: is a request was made by an AWS service account. Many AWS services use service accounts to perform automated actions in my behalf.
2. AssumedRole: is a request was made with temporary credentials obtained by using the AWS Security Token Service (STS) AssumeRole operation.
3. Whereas that: AssumedRoles obfuscate the name of the user who performed the action.

• The question is: How to Interpret the initial identity of an ‘Assumed Role’ CloudTrail log of a "userIdentity" of the type "AWSService", "invokedBy": "sns.amazonaws.com"?

• Follow the log:

{
    "eventVersion": "1.08",
    "userIdentity": {
        "type": "AWSService",
        "invokedBy": "sns.amazonaws.com"
    },
    "eventTime": "2022-07-18T00:00:00Z",
    "eventSource": "sts.amazonaws.com",
    "eventName": "AssumeRole",
    "awsRegion": "us-east-1",
    "sourceIPAddress": "sns.amazonaws.com",
    "userAgent": "sns.amazonaws.com",
    "requestParameters": {
        "roleArn": "arn:aws:iam::1111111111111:role/SNSSuccessFeedback",
        "roleSessionName": "AWS-SNS"
    },
    "responseElements": {
        "credentials": {
            "accessKeyId": "ASIAVY2MDDDDDDDDDDDD",
            "sessionToken": ....,
            "expiration": "Jul 18, 2022, 00:00:00 AM"
        },
        "assumedRoleUser": {
            "assumedRoleId": "AROAVY2MAAAAAAAAAAAAA:AWS-SNS",
            "arn": "arn:aws:sts::1111111111111:assumed-role/SNSSuccessFeedback/AWS-SNS"
        }
    },
    "requestID": "db01-4b68-...-a3f20ac5",
    "eventID": "a78f-49dd-....-098fa88b",
    "readOnly": false,
    "resources": [
        {
            "accountId": "1111111111111",
            "type": "AWS::IAM::Role",
            "ARN": "arn:aws:iam::1111111111111:role/SNSSuccessFeedback"
        }
    ],
    "eventType": "AwsApiCall",
    "managementEvent": true,
    "recipientAccountId": "1111111111111",
    "sharedEventID": "88888888-....-fes343ade",
    "eventCategory": "Management"
}