CVE-2026-70665
Received
Received - Intake
Doorkeeper OpenID Connect Scope Validation Bypass
Vulnerability report for CVE-2026-70665, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-25
Last updated on: 2026-08-25
Assigner: GitHub, Inc.
Description
Description
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.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| doorkeeper | doorkeeper | 1.10.4 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-285 | The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. |
