Detection rules › Panther

S3 Bucket Replication Deleted

Severity
medium
Log types
AWS.CloudTrail
Tags
AWS, Defense Evasion, Impact:Data Destruction
Reference
https://docs.aws.amazon.com/AmazonS3/latest/userguide/replication.html
Source
github.com/panther-labs/panther-analysis

Detects when S3 bucket replication configuration is deleted, which could prevent data backup and indicate ransomware preparation activity.

MITRE ATT&CK coverage

TacticTechniques
StealthT1562 Impair Defenses
ImpactT1485 Data Destruction

Rules detecting the same action

Other rules on this platform that filter on the same API call or operation.

Rule body yaml

AnalysisType: rule
Filename: aws_s3_delete_bucket_replication.py
RuleID: "AWS.S3.DeleteBucketReplication"
DisplayName: "S3 Bucket Replication Deleted"
Enabled: true
LogTypes:
  - AWS.CloudTrail
Tags:
  - AWS
  - Defense Evasion
  - Impact:Data Destruction
Reports:
  MITRE ATT&CK:
    - TA0005:T1562
    - TA0040:T1485
Severity: Medium
Description: Detects when S3 bucket replication configuration is deleted, which could prevent data backup and indicate ransomware preparation activity.
Runbook: |
  1. Query CloudTrail for all S3 API calls by the userIdentity:arn on the requestParameters:bucketName in the 24 hours before and after the replication deletion to establish full activity context
  2. Check if this user has historically managed replication settings for this bucket in the past 90 days to verify if this is authorized administrative work
  3. Find other alerts indicating security control disabling (DeleteBucketEncryption, SuspendVersioning, DisableBucketLogging) for the same bucket in the past 7 days to identify ransomware preparation patterns
Reference: https://docs.aws.amazon.com/AmazonS3/latest/userguide/replication.html
SummaryAttributes:
  - sourceIpAddress
  - userAgent
  - recipientAccountId
  - p_any_aws_arns
Tests:
  - Name: Bucket Replication Deleted Successfully
    ExpectedResult: true
    Log:
      {
        "eventVersion": "1.08",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalId": "AAAAAAAAAAAAAAAAAAAAA:user_name",
            "arn": "arn:aws:sts::111111111111:assumed-role/sample-role-dreamy-yonath/sample-role-brave-yalow-role-intelligent-brahmagupta-role-beautiful-keldysh-role-happy-easley-role-bold-buck",
            "accountId": "111111111111",
            "accessKeyId": "ASIA-MOCKACCESSKEYID-1",
            "sessionContext":
              {
                "attributes":
                  {
                    "mfaAuthenticated": "false",
                    "creationDate": "2024-01-15T10:30:00Z",
                  },
                "sessionIssuer":
                  {
                    "type": "Role",
                    "principalId": "AAAAAAAAAAAAAAAAAAAAA",
                    "arn": "arn:aws:iam::111111111111:role/sample-role-dreamy-yonath",
                    "accountId": "111111111111",
                    "userName": "AdminRole",
                  },
              },
          },
        "eventTime": "2024-01-15T10:45:23Z",
        "eventSource": "s3.amazonaws.com",
        "eventName": "DeleteBucketReplication",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "1.2.3.4",
        "userAgent": "aws-cli/2.13.0 Python/3.11.4 Linux/5.10.0-1234-aws exe/x86_64.ubuntu.22",
        "requestParameters":
          {
            "bucketName": "production-backup-bucket",
            "host": "sample-bucket-serene-pike.s3.amazonaws.com",
            "replication": "",
          },
        "responseElements": null,
        "requestID": "ABC123DEF456",
        "eventID": "12345678-1234-1234-1234-111111111111",
        "readOnly": false,
        "eventType": "AwsApiCall",
        "managementEvent": true,
        "recipientAccountId": "111111111111",
        "vpcEndpointId": "vpce-1a2b3c4d",
      }
  - Name: Bucket Replication Deletion Failed
    ExpectedResult: false
    Log:
      {
        "eventVersion": "1.08",
        "userIdentity":
          {
            "type": "IAMUser",
            "principalId": "AIDAI23HXS4EXAMPLE",
            "arn": "arn:aws:iam::111111111111:user/testuser",
            "accountId": "111111111111",
            "accessKeyId": "AKIA-MOCKACCESSKEYID-1",
          },
        "eventTime": "2024-01-15T10:45:23Z",
        "eventSource": "s3.amazonaws.com",
        "eventName": "DeleteBucketReplication",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "1.2.3.4",
        "userAgent": "aws-cli/2.13.0 Python/3.11.4 Linux/5.10.0-1234-aws exe/x86_64.ubuntu.22",
        "errorCode": "AccessDenied",
        "errorMessage": "Access Denied",
        "requestParameters":
          {
            "bucketName": "production-backup-bucket",
            "host": "sample-bucket-serene-pike.s3.amazonaws.com",
          },
        "responseElements": null,
        "requestID": "ABC123DEF456",
        "eventID": "12345678-1234-1234-1234-111111111111",
        "readOnly": false,
        "eventType": "AwsApiCall",
        "managementEvent": true,
        "recipientAccountId": "111111111111",
      }
  - Name: Different S3 Event
    ExpectedResult: false
    Log:
      {
        "eventVersion": "1.08",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalId": "AAAAAAAAAAAAAAAAAAAAA:user_name",
            "arn": "arn:aws:sts::111111111111:assumed-role/sample-role-dreamy-yonath/sample-role-brave-yalow-role-intelligent-brahmagupta-role-beautiful-keldysh-role-happy-easley-role-bold-buck",
            "accountId": "111111111111",
            "accessKeyId": "ASIA-MOCKACCESSKEYID-1",
          },
        "eventTime": "2024-01-15T10:45:23Z",
        "eventSource": "s3.amazonaws.com",
        "eventName": "PutBucketReplication",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "1.2.3.4",
        "userAgent": "aws-cli/2.13.0 Python/3.11.4 Linux/5.10.0-1234-aws exe/x86_64.ubuntu.22",
        "requestParameters":
          {
            "bucketName": "production-backup-bucket",
            "host": "sample-bucket-serene-pike.s3.amazonaws.com",
          },
        "responseElements": null,
        "requestID": "ABC123DEF456",
        "eventID": "12345678-1234-1234-1234-111111111111",
        "readOnly": false,
        "eventType": "AwsApiCall",
        "managementEvent": true,
        "recipientAccountId": "111111111111",
      }
  - Name: Non-S3 Event
    ExpectedResult: false
    Log:
      {
        "eventVersion": "1.08",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalId": "AAAAAAAAAAAAAAAAAAAAA:user_name",
            "arn": "arn:aws:sts::123456789012:assumed-role/AdminRole/user_name",
            "accountId": "123456789012",
            "accessKeyId": "ASIAIOSFODNN7EXAMPLE",
          },
        "eventTime": "2024-01-15T10:45:23Z",
        "eventSource": "ec2.amazonaws.com",
        "eventName": "DeleteBucketReplication",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "203.0.113.42",
        "userAgent": "aws-cli/2.13.0 Python/3.11.4 Linux/5.10.0-1234-aws exe/x86_64.ubuntu.22",
        "requestParameters": {},
        "responseElements": null,
        "requestID": "ABC123DEF456",
        "eventID": "12345678-1234-1234-1234-123456789012",
        "readOnly": false,
        "eventType": "AwsApiCall",
        "managementEvent": true,
        "recipientAccountId": "123456789012",
      }

Detection logic

Condition

not (errorCode is_not_null or errorMessage is_not_null)
eventSource eq "s3.amazonaws.com"
eventName eq "DeleteBucketReplication"

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
errorCodeis_not_null(no value, null check)
errorMessageis_not_null(no value, null check)

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
eventNameeq
  • DeleteBucketReplication
eventSourceeq
  • s3.amazonaws.com

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

FieldSource
eventName
eventSource
awsRegion
recipientAccountId
sourceIPAddress
userAgent
userIdentity
actor_user
bucketNamerequestParameters.bucketName