detection-rules
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AWS EC2 Export Task

Identifies successful export tasks of EC2 instances via the APIs CreateInstanceExportTask, ExportImage, or CreateStoreImageTask. These exports can be used by administrators for legitimate VM migration or backup workflows however, an attacker with access to an EC2 instance or AWS credentials can export a VM or its image and then transfer it off-account for exfiltration of data.

Rule type: query
Rule indices:

  • filebeat-*
  • logs-aws.cloudtrail-*

Rule Severity: medium
Risk Score: 47
Runs every:
Searches indices from: now-6m
Maximum alerts per execution: ?
References:

Tags:

  • Domain: Cloud
  • Data Source: AWS
  • Data Source: Amazon Web Services
  • Data Source: AWS EC2
  • Use Case: Asset Visibility
  • Tactic: Exfiltration
  • Tactic: Collection
  • Resources: Investigation Guide

Version: ?
Rule authors:

  • Elastic

Rule license: Elastic License v2

Disclaimer: This investigation guide was created using generative AI technology and has been reviewed to improve its accuracy and relevance. While every effort has been made to ensure its quality, we recommend validating the content and adapting it to suit your specific environment and operational needs.

The APIs CreateInstanceExportTask, ExportImage, and CreateStoreImageTask allow the export of a running or stopped EC2 instance (or its AMI/image) to external storage (e.g., S3) or image formats. While often used for migration, cloning or backup, adversaries can leverage these actions to copy full VM state or images out of the environment for exfiltration.

Identify the actor and context

  • Check aws.cloudtrail.user_identity.arn, aws.cloudtrail.user_identity.type, aws.cloudtrail.user_identity.access_key_id to identify who made the call.
  • Verify user_agent.original, source.ip and @timestamp to determine whether the action is by known automation, trusted operator, or an unexpected identity or location.
  • Confirm cloud.account.id and cloud.region match the expected account/region for export tasks.

Examine the specific export/image task details

  • Review aws.cloudtrail.request_parameters for details such as the InstanceId, TargetEnvironment, S3Bucket, S3Key, DiskImageFormat, ContainerFormat.
  • Check aws.cloudtrail.response_elements for the resulting export task ID and status.
  • Determine whether the exported instance or image contained sensitive workloads (e.g., production databases, critical systems) via instance tags or asset inventory.

Pivot to related API calls/events

  • Look for follow-on tasks such as:
    • S3 bucket writes or cross-account bucket ACL changes (PutBucketAcl/PutBucketPolicy) referencing the export S3 bucket or key.
    • CopyImage, ModifyImageAttribute, or ShareImage events if the exported image is copied or shared.
    • Network or usage anomalies in the region or from the S3 bucket (large downloads from the exported object).
  • Check for preceding suspicious actions that could indicate compromise: AssumeRole, CreateAccessKey, AttachUserPolicy, or unusual Describe* operations.

Assess legitimacy and risk

  • Confirm whether this export was authorized (via change ticket or migration workflow) and whether the principal has a documented justification for VM export.
  • If unauthorized, assess what was exported, where it is stored, how it may be transferred or used externally, and the data risk exposure.
  • Legitimate migration or backup workflows may trigger these export/image APIs.
  • Development/test environments may export VM images or instances for sandbox cloning.
  • Known automation tools may create exports at scheduled times.
  • Immediately identify and disable or isolate any object/resource created by the export (e.g., the S3 bucket/object, image ID) that is suspected of unauthorized use.
  • Revoke the access credentials (aws.cloudtrail.user_identity.access_key_id) used if they show unusual activity.
  • Rotate keys, enforce MFA, and review IAM permissions for the principal.
  • Audit the exported VM/image: review its contents if possible, check whether it has been moved off-account.
  • Strengthen monitoring: set alerts for subsequent large data transfers from the S3 export location, cross-account sharing of exported images, or anomalous AMI imports.
  • Update policy: restrict who can perform exports, monitor export actions via AWS Config or CloudTrail, tag and track export tasks and their destinations.
event.dataset: "aws.cloudtrail" and
    event.provider: "ec2.amazonaws.com" and
    event.action: ("CreateInstanceExportTask" or "ExportImage" or "CreateStoreImageTask") and
    event.outcome: "success"

Framework: MITRE ATT&CK

Framework: MITRE ATT&CK