Doorkeeper OpenID Connect: DCR endpoint persists unvalidated client-supplied scopes (CVE-2026-70665) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-70665

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

Answer in brief

CVE-2026-70665 records a Unknown severity vulnerability in Doorkeeper OpenID Connect: DCR endpoint persists unvalidated client-supplied scopes. The current sources do not mark it as known exploited. The current feed maps doorkeeper-gem/doorkeeper-openid_connect (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 25, 2026Updated Aug 25, 2026Source checked Aug 25, 2026First seen by HOL Aug 25, 2026Material review Aug 25, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps doorkeeper-gem/doorkeeper-openid_connect (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
doorkeeper-gem/doorkeeper-openid_connectgeneric	< 1.10.4	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for doorkeeper-gem/doorkeeper-openid_connect.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Aug 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 25, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.