Auth bypass in Red Hat Build Of Keycloak
CVE-2026-118959
A flaw was found in the required action provider mechanism of Keycloak. The issue occurs when an authorization request includes the kc_action query parameter set to a mandatory action already assigned to the user, such as profile verification or terms and conditions. Due to incorrect handling of application-initiated actions, Keycloak may skip these mandatory challenges and issue an authorization code. This can allow a user to bypass administrative requirements and gain access to the application without completing necessary profile updates or agreeing to terms.
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-2026-118959 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
Frequently asked questions
- What is CVE-2026-118959?
- CVE-2026-118959 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Improper Authentication. CVSS score: 5.4/10. Published 2026-10-30.
- How severe is CVE-2026-118959?
- Medium severity. CVSS v3 base score is 5.4 out of 10.