Auth bypass in Red Hat Build Of Keycloak
CVE-2026-105306
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.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-105306 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
Frequently asked questions
- What is CVE-2026-105306?
- CVE-2026-105306 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Missing Authorization. CVSS score: 6.5/10. Published 2026-10-05.
- How severe is CVE-2026-105306?
- Medium severity. CVSS v3 base score is 6.5 out of 10.