Information Disclosure in Amazon ECS Container Agent
Date: 2025-08
Affected: go/github.com/aws/amazon-ecs-agent
Attack vector: info-disclosure
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2025-9039
CWE: CWE-200
CWE-277
CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N)

**Summary** [Amazon Elastic Container Service (Amazon ECS)](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/Welcome.html) is a fully managed container orchestration service that enables customers to deploy, manage, and scale containerized applications. Amazon ECS container agent provides an [introspection API](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/introspection-diag.html) that provides information about the overall state of the Amazon ECS agent and the container instances. We identified CVE-2025-9039, an issue in the Amazon ECS agent. **Impact** Under certain conditions, this issue could allow an introspection server to be accessed off-host by another instance if the instances are in the same security group or if their security groups allow incoming connections that include the port where the server is hosted. This issue does not affect instances where the option to allow off-host access to the introspection server is set to 'false'. Impacted versions: version 0.0.3 through 1.97.0 **Patches** This issue has been addressed in ECS agent version 1.97.1. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes. **Workarounds** Customers who cannot update to the latest AMI can modify the Amazon EC2 security groups to restrict incoming access to the introspection server port (51678). **References** If you have any questions or comments about this advisory, we ask that


Mitigations:

Architectural layers (MAESTRO):