CVE-2026-89419 in Ironic
Summary
by MITRE • 10/23/2026
OpenStack Ironic before 39.0.1 sometimes allows a user to change the maintenance setting on a node via PATCH to /v1/nodes/{ident} - in other words, not using the specific maintenance endpoint.
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Analysis
by VulDB Data Team • 10/23/2026
The vulnerability identified in OpenStack Ironic prior to version 39.0.1 represents an authorization bypass flaw within the RESTful API implementation of the bare metal provisioning service. Specifically, this issue stems from a failure to enforce strict access control policies on certain HTTP methods when interacting with node resources. The core technical deficiency lies in how the framework processes PATCH requests directed at the general nodes endpoint, identified by the path /v1/nodes/{ident}. In a properly secured architecture, administrative actions such as altering the maintenance state of a physical server should be restricted to dedicated endpoints or require explicit verification that the request method aligns with the intended operation scope. However, in this affected version, the API handler for PATCH requests on the general node resource incorrectly permits modifications to fields that are typically reserved for specific management operations, thereby circumventing the security controls designed to isolate privileged actions from standard operational updates.
From a technical perspective, the maintenance mode setting is a critical state variable within Ironic that determines whether a node is available for provisioning or locked down for administrative tasks such as hardware inspection, firmware updates, or troubleshooting. By allowing this attribute to be modified via a generic PATCH request rather than forcing the use of the dedicated maintenance endpoint, the system exposes an unintended attack vector. An authenticated user with permissions sufficient to update general node attributes can inadvertently or maliciously toggle the maintenance flag without triggering the additional validation checks that are typically associated with the specialized maintenance API path. This inconsistency in policy enforcement creates a gap where state-altering operations bypass the intended security boundaries defined by the application's role-based access control model.
The operational impact of this vulnerability is significant, particularly in multi-tenant environments or when Ironic manages critical infrastructure components. An attacker who gains valid credentials with limited privileges could exploit this flaw to place nodes into maintenance mode without authorization. This action effectively removes those servers from the pool of available resources for provisioning new workloads, leading to a denial of service condition for legitimate users attempting to deploy instances. Furthermore, if an adversary can toggle maintenance status repeatedly or in conjunction with other vulnerabilities, they may disrupt automated workflows that rely on predictable node availability states. In more severe scenarios, manipulating the maintenance state could interfere with hardware management processes, potentially causing data corruption during firmware updates or preventing necessary diagnostic procedures from executing correctly.
To mitigate this risk, organizations running OpenStack Ironic must upgrade to version 39.0.1 or later, where the access control policies have been corrected to restrict PATCH operations on node resources appropriately. Until an upgrade is feasible, administrators should implement network-level controls such as firewall rules that block direct API access from untrusted networks and ensure that only authorized service accounts can interact with the Ironic endpoint. Additionally, auditing logs for unusual patterns of PATCH requests targeting node identifiers can help detect potential exploitation attempts in real-time. It is also advisable to review role definitions within Keystone to ensure that users do not possess excessive permissions on general node attributes if they should be restricted to read-only or specific update scopes excluding state-altering fields like maintenance status.
This vulnerability aligns with CWE-269, which describes Improper Privilege Management, as it involves a user obtaining privileges or performing actions beyond their intended scope due to flawed access control logic. It also relates to CWE-732, concerning Incorrect Permission Assignment for Critical Resource, because the resource attribute in question requires elevated permissions that were inadvertently exposed through an insufficiently restricted API method. In terms of offensive security frameworks, this flaw can be leveraged within the MITRE ATT&CK technique T1098, specifically under the sub-technique related to Account Manipulation or Access Token Modification, as it allows for unauthorized changes to system state that affect resource availability and management capabilities. Addressing these gaps is essential for maintaining the integrity and reliability of bare metal infrastructure managed by OpenStack Ironic.