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.
Affected products
openstack: keystone
References5
- security.openstack.org/ossa/OSSA-2026-015.html PatchVendor Advisory
- bugs.launchpad.net/keystone/+bug/2148477 ExploitIssue TrackingPatchThird Party Advisory
- access.redhat.com/security/cve/CVE-2026-43000
- bugzilla.redhat.com/show_bug.cgi?id=2482826
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43000…
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 26 · as of 15 November 2026
- CWE
- CWE-863CWE-266
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.