OSSN-0106: Ironic API ramdisk endpoints require network-level access controls

Summary

The Ironic Bare Metal API combines authenticated endpoints for client use with unauthenticated endpoints for coordination with the Ironic Python Agent ramdisk into a single API service. Depending on the deployment architecture, this can expose security risks if the unauthenticated endpoints are reachable from untrusted networks.

Affected Services / Software

• ironic (>=6.2.0) - /v1/lookup and /v1/heartbeat: API version 1.22 (Newton, ironic 6.2.0) - /v1/continue_inspection: API version 1.84 (2024.2)

Discussion

Ironic has three endpoints which allow unauthenticated access:

• GET /v1/lookup

• POST /v1/heartbeat/{node_ident}

• POST /v1/continue_inspection

These endpoints are a documented aspect of Ironic’s architecture and are covered in the Ironic security guide. They already have significant security controls to mitigate risk, such as bootstrapping into credentials via the agent token mechanism (mandatory since the Victoria release), callback URL validation, and defaulting to limiting access to nodes whose provisioning state requires use of them.

Regardless of authentication methodology, operators in multi-tenant or untrusted environments should deploy a split-horizon API configuration where the unauthenticated endpoints are not reachable from public or tenant networks. Using Keystone does not eliminate the need for this network-level separation. Previously, Ironic only provided policy-based overrides to disable these endpoints, which required Keystone and left operators using HTTP basic auth or noauth without an equivalent control. A new [api]enable_ramdisk_endpoints configuration option is being added to allow any operator, regardless of authentication methodology, to disable these endpoints on a per-service basis.

For full details on the security model around these endpoints, refer to the Ironic security guide: https://docs.openstack.org/ironic/latest/admin/security.html

Recommended Actions

Operators using Ironic in a multi-tenant or untrusted environment should configure the Ironic API so that the unauthenticated endpoints are only accessible from networks where the Ironic Python Agent ramdisk operates. This can be achieved in several ways depending on infrastructure setup:

1. Run separate public-facing and ramdisk-facing Ironic API services.

Warning: Disabling the ramdisk endpoints without maintaining a separate API service that the Ironic Python Agent can reach will break all deployment, cleaning, inspection, rescue, and servicing workflows. These endpoints must remain available to the ramdisk on at least one API service.

On the public-facing service, disable the ramdisk endpoints using one of the following methods:

• Set [api]enable_ramdisk_endpoints to False in ironic.conf (anticipated in the 2026.2 Hibiscus cycle, ironic 39.0.0; available earlier by applying the linked patch).

• For Keystone-authenticated deployments, add the following to policy.yaml:

  "baremetal:node:ipa_heartbeat": "!"
  "baremetal:driver:ipa_lookup": "!"
  "baremetal:driver:ipa_continue_inspection": "!"
  

When using this architecture, the [deploy]external_callback_url setting can direct the agent callback URL to the internal API service, and the [service_catalog]endpoint_override setting can override Ironic’s own internal endpoint resolution, if required.

2. Use a fronting HTTP proxy, WSGI runner, or other external method to restrict access to /v1/lookup, /v1/heartbeat, and /v1/continue_inspection to only networks which run the Ironic Python Agent. This method requires no Ironic code changes.

3. Ensure [api]restrict_lookup remains set to its default value of True. Disabling this setting removes state-based filtering on the lookup endpoint and significantly broadens exposure.

Credits:

• Tuomo Tanskanen, Ericsson Software Technology (Metal3.io Security Team),

• Dmitry Tantsur, Red Hat (Metal3.io Security Team)

Contacts / References

Author: Julia Kreger (Red Hat), Jay Faulkner (G-Research OSS)

• This OSSN : https://docs.openstack.org/security-notes/OSSN-0106.html

• Original Launchpad bug : https://bugs.launchpad.net/ironic/+bug/2162821

• Original Launchpad bug : https://bugs.launchpad.net/ironic/+bug/2162818

• Proposed enhancement : https://review.opendev.org/c/openstack/ironic/+/999897

• Mailing List : openstack-discuss@lists.openstack.org

• OpenStack Security : https://security.openstack.org/