CVE-2026-70665

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 v3 4.2 MEDIUM

4.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/doorkeeper-gem/doorkeeper-openid_connect/commit/24c3cb1729b69f48649a6f4491dcae69f805000d
https://github.com/doorkeeper-gem/doorkeeper-openid_connect/security/advisories/GHSA-8r7r-wh7x-27ff

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 23:17

Updated : 2026-09-09 21:09

NVD link : CVE-2026-70665

Mitre link : CVE-2026-70665

CVE.ORG link : CVE-2026-70665

JSON object : View

Products Affected

No product.

CWE

CWE-285

Improper Authorization

{"id": "CVE-2026-70665", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-70665", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-27T13:52:58.639766Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.2, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 1.6}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "doorkeeper-gem", "product": "doorkeeper-openid_connect", "versions": [{"status": "affected", "version": "< 1.10.4"}]}]}], "published": "2026-08-25T23:17:58.933", "references": [{"url": "https://github.com/doorkeeper-gem/doorkeeper-openid_connect/commit/24c3cb1729b69f48649a6f4491dcae69f805000d", "source": "security-advisories@github.com"}, {"url": "https://github.com/doorkeeper-gem/doorkeeper-openid_connect/security/advisories/GHSA-8r7r-wh7x-27ff", "source": "security-advisories@github.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-285"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-09-09T21:09:13.080", "sourceIdentifier": "security-advisories@github.com"}