CVE Catalog

CVE-2026-70665

MediumCVSS 4.2
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

6th percentile - higher than 6% of all known CVEs

Summary

Doorkeeper OpenID Connect prior to 1.10.4 does not validate client-supplied scopes during Dynamic Client Registration (DCR). This allows a self-registered client to obtain scopes beyond what the server intended to grant, leading to privilege escalation.

Risk Assessment

An attacker could register their own client and gain access to protected resources with scopes they should not have, potentially compromising data confidentiality.

Recommendation

Upgrade to version 1.10.4 or later and enable enforce_configured_scopes.

Related vulnerabilities

Original NVD description (English source)

Doorkeeper OpenID Connect implements an OpenID Connect authentication provider for Rails applications on top of Doorkeeper. Prior to 1.10.4, the Dynamic Client Registration (DCR) endpoint persists client-supplied scopes without validating them against the server's configured scope set. Under certain conditions, this allows a self-registered client to obtain scopes beyond what the server intended to grant. In DynamicClientRegistrationController#application_params, the scopes attribute is assigned directly from params[:scope] with no validation against Doorkeeper.configuration.scopes or optional_scopes. Combined with enforce_configured_scopes being off by default and Doorkeeper's ScopeChecker prioritizing application-level scopes over server-level scopes, this creates a privilege escalation path. This issue is fixed in version 1.10.4.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS