CVE-2026-43000: openstack keystone Incorrect Authorization

Vulnerability summary

CVE-2026-43000 is a high (CVSS 8.8) Incorrect Authorization vulnerability in openstack keystone. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 25.9% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 28-05-2026
   PublishedVulnerability first disclosed.
2. 24-07-2026
   Last modifiedVulnerability information updated.

Description

An issue was discovered in OpenStack Keystone before 29.0.2. When combined with an application credential impersonation vulnerability, an attacker with the member role on a project can escalate to admin by chaining unrestricted application credentials with Keystone trusts. The impersonated token carries the victim's identity, which passes the trustor validation check. Keystone then validates the delegated roles against the victim's actual role assignments in the database, not the roles on the requesting token. This allows the attacker to create a trust delegating the victim's admin role to themselves. The trust persists independently, and additional trusts and application credentials can be created to maintain access. All actions are logged under the victim's identity.

• CWE-863Incorrect AuthorizationThe product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
• CWE-266Incorrect Privilege AssignmentA product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor.