DeleteBucketPolicy
AWS
DeleteBucketPolicy
Event
Removes the resource-based policy from an S3 bucket, reverting to default access controls.
Security Context
- Impairing defenses allows adversaries to operate freely by removing security controls that would otherwise detect or block their activity.
- Accessing cloud storage objects can expose sensitive data including backups, configuration files, application data, and customer information.
Log Source
CloudTrail
Sample Event
Adversarial. Draco removes the bucket policy on fantasticlogs-niffler-archive so that a previously-restrictive resource policy (e.g., one that limited access to OccamyPipelineRole) is gone. Subsequent cross-account GetObject calls from 555666661337 will then succeed. This is the T1685 defense-impairment + T1530 collection setup.
{ "eventVersion": "1.09", "userIdentity": { "type": "IAMUser", "principalId": "AIDADRAC0MALF0YBADGY", "arn": "arn:aws:iam::555123456789:user/draco", "accountId": "555123456789", "accessKeyId": "ASIADRAC0MALF0YEXAMP5", "userName": "draco", "sessionContext": { "attributes": { "creationDate": "2026-04-15T19:02:11Z", "mfaAuthenticated": "false" } } }, "eventTime": "2026-04-15T20:14:02Z", "eventSource": "s3.amazonaws.com", "eventName": "DeleteBucketPolicy", "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": "fantasticlogs-niffler-archive", "Host": "fantasticlogs-niffler-archive.s3.us-east-1.amazonaws.com" }, "responseElements": null, "additionalEventData": { "SignatureVersion": "SigV4", "CipherSuite": "ECDHE-RSA-AES128-GCM-SHA256", "bytesTransferredIn": 0, "AuthenticationMethod": "AuthHeader", "bytesTransferredOut": 0 }, "requestID": "90000000-0000-4000-8000-000011010000", "eventID": "90000000-0000-4000-8000-000011010001", "readOnly": false, "resources": [ { "accountId": "555123456789", "type": "AWS::S3::Bucket", "ARN": "arn:aws:s3:::fantasticlogs-niffler-archive" } ], "eventType": "AwsApiCall", "managementEvent": true, "recipientAccountId": "555123456789", "eventCategory": "Management", "tlsDetails": { "tlsVersion": "TLSv1.3", "cipherSuite": "TLS_AES_128_GCM_SHA256", "clientProvidedHostHeader": "fantasticlogs-niffler-archive.s3.us-east-1.amazonaws.com" }}MITRE ATT&CK Mapping
Tactics: Collection
Techniques:
- T1530 — Data from Cloud Storage — Adversaries may access data from cloud storage.