OpenStack Keystone's federated token rescoping mechanism doesn't propagate the original token's expiry to the newly issued token
Moderate severity
GitHub Reviewed
Published
May 28, 2026
to the GitHub Advisory Database
•
Updated Jul 2, 2026
Package
Affected versions
>= 14.0.0, < 27.0.2
>= 28.0.0, < 28.0.2
>= 29.0.0, < 29.0.2
Patched versions
27.0.2
28.0.2
29.0.2
Description
Published by the National Vulnerability Database
May 28, 2026
Published to the GitHub Advisory Database
May 28, 2026
Reviewed
Jul 2, 2026
Last updated
Jul 2, 2026
An issue was discovered in OpenStack Keystone before 29.0.2. The Keystone federated token rescoping mechanism does not propagate the original token's expiry to the newly issued token. When a federated user rescopes a token via POST /v3/auth/tokens, the handle_scoped_token() function in the mapped authentication plugin returns response data without an expires_at value. The token provider falls back to issuing a token with a fresh default TTL. By rescoping repeatedly before each token expires, a user can maintain access indefinitely, bypassing operator-configured token lifetime policies. This is a variant of CVE-2012-3426. Only deployments using federated identity (SAML2, OpenID Connect) are affected.
References