High [CVE-2026-2035366] Application credential tokens can escape project scope via token-method reauthentication
This high-severity Red Hat Linux advisory covers CVE-2026-2035366.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
A flaw was found in OpenStack Keystone where an application credential token can escape its intended project scope through token-method reauthentication. Keystone rejects an explicit scope change for an application credential token, but an omitted scope falls through to the owner's default project.
If the owner has roles on that default project, Keystone issues a new token scoped there while still carrying the original application credential identity. Custom Keystone authentication plugins are subject to the same incomplete rescope guard.
This allows a limited-scope application credential for one project to access another project within the owner's role assignments. This vulnerability is rated as Important because an authenticated user with an application credential can escape the credential's project binding through token reauthentication and access the owner's default project.
Application credential reauthentication only becomes practically exploitable from Keystone 27.0.1 on the 27.x stable line, and from 28.0.0 on the 28.x line. On earlier versions, exchanging an application credential token fails before a new token is issued.
Red Hat OpenStack Platform 16.2, 17.1, and 18.0 (including RHOSO) ship openstack-keystone versions below 27.0.1 and are not affected.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Mitigation checklist
- Set the following in keystone.conf to prevent exchanging a scoped token for a token with a different project scope: [token] allow_rescope_scoped_token = False This blocks the application-credential default-project fallback. It also prevents Horizon project switching for users who authenticate with a scoped token. This setting does not disable application credentials themselves.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.