CVE-2026-42998
An attacker can authenticate with their own application credential ID and secret while specifying a different user's name and domain in the request body.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
An issue was discovered in OpenStack Keystone before 29.0.2. The Keystone application credential authentication plugin does not verify that the user supplied in the authentication request matches the owner of the application credential. An attacker can authenticate with their own application credential ID and secret while specifying a different user's name and domain in the request body. Keystone issues a token attributed to the victim user. The impersonated token is project-scoped and carries the intersection of the application credential's roles and the victim's actual roles on the project. This enables audit evasion, reading the victim's credentials, and acting as the victim within shared projects.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.30% probability · 23th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-863
- Affected
- openstack/keystone
- Source
- cve@mitre.org
References
- https://bugs.launchpad.net/keystone/+bug/2148477Exploit, Issue Tracking, Patch, Third Party Advisory
- https://security.openstack.org/ossa/OSSA-2026-015.htmlPatch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.