Auth bypass in Red Hat Build Of Keycloak
CVE-2026-105305
A flaw was found in the OIDC implementation of Keycloak, specifically within the Device Authorization Grant flow. This component allows devices with limited input capabilities to obtain security tokens. The issue occurs because the flow fails to check the minimum authentication level required by a client configuration. This allows an attacker who has stolen a user's password to bypass mandatory multi-factor authentication and gain unauthorized access to the Keycloak Admin REST API.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/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-2026-105305 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
Frequently asked questions
- What is CVE-2026-105305?
- CVE-2026-105305 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Improper Authentication. CVSS score: 5.4/10. Published 2026-10-06.
- How severe is CVE-2026-105305?
- Medium severity. CVSS v3 base score is 5.4 out of 10.