A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials.
History

Tue, 19 May 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 19 May 2026 14:30:00 +0000

Type Values Removed Values Added
First Time appeared Redhat build Of Keycloak
Vendors & Products Redhat build Of Keycloak

Tue, 19 May 2026 12:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-200
CWE-284

Tue, 19 May 2026 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Moderate


Tue, 19 May 2026 11:30:00 +0000

Type Values Removed Values Added
Description A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials.
Title Keycloak: keycloak: information disclosure via oidc token introspection endpoint audience bypass
First Time appeared Redhat
Redhat build Keycloak
CPEs cpe:/a:redhat:build_keycloak:
Vendors & Products Redhat
Redhat build Keycloak
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-05-19T13:40:07.406Z

Reserved: 2026-04-06T07:48:39.722Z

Link: CVE-2026-37979

cve-icon Vulnrichment

Updated: 2026-05-19T13:40:04.125Z

cve-icon NVD

Status : Undergoing Analysis

Published: 2026-05-19T12:16:18.330

Modified: 2026-05-19T15:16:30.477

Link: CVE-2026-37979

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-05-19T00:00:00Z

Links: CVE-2026-37979 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-05-19T14:30:06Z