T1552.007: Container API

Adversaries may gather credentials via APIs within a containers environment. APIs in these environments, such as the Docker API and Kubernetes APIs, allow a user to remotely manage their container resources and cluster components.

An adversary may access the Docker API to collect logs that contain credentials to cloud, container, and various other resources in the environment. An adversary with sufficient permissions, such as via a pod's service account, may also use the Kubernetes API to retrieve credentials from the Kubernetes API server. These credentials may include those needed for Docker API authentication or secrets from Kubernetes cluster components.

Detection

IDDS0002Data source and componentUser Account: User Account AuthenticationDescription

It may be possible to detect adversary use of credentials they have obtained such as in Valid Accounts.

IDDS0017Data source and componentCommand: Command ExecutionDescription

Establish centralized logging for the activity of container and Kubernetes cluster components. Monitor logs for actions that could be taken to gather credentials to container and cloud infrastructure, including the use of discovery API calls by new or unexpected users and APIs that access Docker logs.

Mitigation

IDM1026NamePrivileged Account ManagementDescription

Use the principle of least privilege for privileged accounts such as the service account in Kubernetes. For example, if a pod is not required to access the Kubernetes API, consider disabling the service account altogether.

IDM1035NameLimit Access to Resource Over NetworkDescription

Limit communications with the container service to managed and secured channels, such as local Unix sockets or remote access via SSH. Require secure port access to communicate with the APIs over TLS by disabling unauthenticated access to the Docker API and Kubernetes API Server. In Kubernetes clusters deployed in cloud environments, use native cloud platform features to restrict the IP ranges that are permitted to access to API server. Where possible, consider enabling just-in-time (JIT) access to the Kubernetes API to place additional restrictions on access.

IDM1030NameNetwork SegmentationDescription

Deny direct remote access to internal systems through the use of network proxies, gateways, and firewalls.

IDM1018NameUser Account ManagementDescription

Enforce authentication and role-based access control on the container API to restrict users to the least privileges required. When using Kubernetes, avoid giving users wildcard permissions or adding users to the system:masters group, and use RoleBindings rather than ClusterRoleBindings to limit user privileges to specific namespaces.