CVE-2026-37979

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:19596	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:19597	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-37979	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2455328	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-19 12:16

Updated : 2026-06-17 10:41

NVD link : CVE-2026-37979

Mitre link : CVE-2026-37979

CVE.ORG link : CVE-2026-37979

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-284

Improper Access Control

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