CVE-2026-105306 PUBLISHED

Keycloak-services: keycloak-services: token introspection audience bypass via dynamic client registration

Assigner: redhat
Reserved: 05.10.2026 Published: 05.10.2026 Updated: 05.10.2026

A flaw was found in the Dynamic Client Registration flow of the Keycloak identity and access management server. The issue occurs because the registration process fails to filter security-sensitive client attributes when a new client is created. An attacker with a valid Initial Access Token can register a client that bypasses audience checks during token introspection. This allows the attacker to view sensitive identity information, roles, and session details from access tokens belonging to other applications in the same realm.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 6.5

Product Status

Vendor Red Hat
Product Red Hat Build of Keycloak
Versions Default: affected
Vendor Red Hat
Product Red Hat Build of Keycloak
Versions Default: affected
Vendor Red Hat
Product Red Hat Single Sign-On 7
Versions Default: unaffected

Workarounds

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Credits

  • Red Hat would like to thank Dung Dang Tien for reporting this issue.

References

Problem Types

  • Missing Authorization CWE