CVE-2026-37979

MEDIUM

Keycloak: keycloak: information disclosure via oidc token introspection endpoint audience bypass

Title source: cna
STIX 2.1

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.

References (4)

Core 4
Core References
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:19596
https://access.redhat.com/errata/RHSA-2026:19596
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:19597
https://access.redhat.com/errata/RHSA-2026:19597
Vdb Entry, X_Refsource_Redhat vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-37979
Issue Tracking, X_Refsource_Redhat issue-tracking x_refsource_redhat
RHBZ#2455328
https://bugzilla.redhat.com/show_bug.cgi?id=2455328

Scores

CVSS v3 6.5
EPSS 0.0001
EPSS Percentile 1.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-284
Status published
Products (4)
Red Hat/Red Hat Build of Keycloak
Red Hat/Red Hat build of Keycloak 26.4 26.4-17
Red Hat/Red Hat build of Keycloak 26.4 26.4.12-1
Red Hat/Red Hat build of Keycloak 26.4.12
Published May 19, 2026
Tracked Since May 19, 2026