Medium 4.2Published Aug 25, 2026

CVE-2026-70665Doorkeeper OpenID Connect: DCR endpoint persists unvalidated client-supplied scopes

Updated under an hour ago (2026-10-19 06:20 UTC)

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Every CVE for doorkeeper-gem doorkeeper-openid_connect

Exploited in the last 30 days

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: 4.2 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
Weakness (CWE): CWE-285
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Aug 27, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

doorkeeper-gem doorkeeper-openid_connect doorkeeper_gem:doorkeeper_openid_connect (from the name)	before 1.10.4	CNA record

References

https://github.com/doorkeeper-gem/doorkeeper-openid_connect/security/advisories/GHSA-8r7r-wh7x-27ffx-refsource-confirm
https://github.com/doorkeeper-gem/doorkeeper-openid_connect/commit/24c3cb1729b69f48649a6f4491dcae69f805000dx-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.