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CopyObject

AWS

CopyObject

service: AWS - S3
techniques:

Event

Copies an object from one S3 location to another, within or across buckets, optionally modifying metadata or encryption.

Security Context

  • Accessing cloud storage objects can expose sensitive data including backups, configuration files, application data, and customer information.
  • Transferring data to external cloud accounts or regions can bypass network-based data loss prevention controls and exfiltrate large volumes of data.

Log Source

CloudTrail

Sample Event

Draco copies a sensitive object from fantasticlogs-niffler-archive (high-value PII) into the adversary-controlled bucket draco-exfil-bucket-666 in his external account. The destination is us-west-2 to evade region-based DLP, and SSE-KMS is dropped on the destination — the adversary doesn’t want the receiving copy encrypted with the victim’s CMK. T1530 + T1537.

{
"eventVersion": "1.09",
"userIdentity": {
"type": "IAMUser",
"principalId": "AIDADRAC0MALF0YBADGY",
"arn": "arn:aws:iam::555123456789:user/draco",
"accountId": "555123456789",
"accessKeyId": "AKIADRAC0MALF0YEXAMP5",
"userName": "draco",
"sessionContext": {
"attributes": {
"creationDate": "2026-04-15T18:51:02Z",
"mfaAuthenticated": "false"
}
}
},
"eventTime": "2026-04-15T19:38:54Z",
"eventSource": "s3.amazonaws.com",
"eventName": "CopyObject",
"awsRegion": "us-east-1",
"sourceIPAddress": "203.0.113.66",
"userAgent": "[aws-cli/1.18.147 Python/3.7.10 Linux/5.4.0-1045-aws botocore/1.18.6]",
"requestParameters": {
"bucketName": "draco-exfil-bucket-666",
"Host": "draco-exfil-bucket-666.s3.us-west-2.amazonaws.com",
"x-amz-copy-source": "fantasticlogs-niffler-archive/customers/2026-q1/customer-pii-export.parquet",
"key": "stolen/customer-pii-export.parquet"
},
"responseElements": null,
"additionalEventData": {
"SignatureVersion": "SigV4",
"CipherSuite": "ECDHE-RSA-AES128-GCM-SHA256",
"bytesTransferredIn": 0.0,
"AuthenticationMethod": "AuthHeader",
"x-amz-id-2": "fqzX1iZV6ImDtkFxbGvziOE6fUwryRa+PhnLckfVAkLNHdbCAHNq4l/yckUd1a2HNJPL6NAS01U=",
"bytesTransferredOut": 4827193.0
},
"requestID": "90000000-0000-4000-8000-000000001001",
"eventID": "90000000-0000-4000-8000-000000001010",
"readOnly": false,
"resources": [
{
"type": "AWS::S3::Object",
"ARN": "arn:aws:s3:::draco-exfil-bucket-666/stolen/customer-pii-export.parquet"
},
{
"accountId": "555666661337",
"type": "AWS::S3::Bucket",
"ARN": "arn:aws:s3:::draco-exfil-bucket-666"
},
{
"accountId": "555123456789",
"type": "AWS::S3::Bucket",
"ARN": "arn:aws:s3:::fantasticlogs-niffler-archive"
},
{
"type": "AWS::S3::Object",
"ARN": "arn:aws:s3:::fantasticlogs-niffler-archive/customers/2026-q1/customer-pii-export.parquet"
}
],
"eventType": "AwsApiCall",
"managementEvent": false,
"recipientAccountId": "555123456789",
"eventCategory": "Data",
"tlsDetails": {
"tlsVersion": "TLSv1.3",
"cipherSuite": "TLS_AES_128_GCM_SHA256",
"clientProvidedHostHeader": "draco-exfil-bucket-666.s3.us-west-2.amazonaws.com"
}
}

MITRE ATT&CK Mapping

Tactics: Collection Exfiltration

Techniques:
  • T1530 — Data from Cloud Storage — Adversaries may access data from cloud storage.
  • T1537 — Transfer Data to Cloud Account — Adversaries may exfiltrate data by transferring the data, including through sharing/syncing and creating backups of cloud environments, to another cloud account they control on the same service.