CVE-2026-97847highCWE-287

CVE-2026-97847: high-severity vulnerability in Red Hat build of Keycloak 26.4

Keycloak-services: keycloak-services: client manager can substitute sessionless token principal via hardcoded-claim mappers to obtain realm administrator authority

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.1epss 0.3%
A flaw was found in the protocol mapper and identity resolution components of Keycloak. The issue occurs when a client manager uses hardcoded-claim mappers to override identity claims in sessionless service-account tokens. Because these tokens lack a session ID, Keycloak may incorrectly resolve the token bearer as a different, highly privileged user based on the manipulated claims. This can allow an attacker with limited client management permissions to impersonate a realm administrator and gain full control over the realm.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L
Affected products
Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.17Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.8Red Hat · Red Hat Single Sign-On 7
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