Vulnerability in Red Hat Build Of Keycloak

CVE-2026-16442

A flaw was found in the SAML broker component of Keycloak, which is used to manage identity federation and user authentication. The issue occurs because the IdP-initiated Single Sign-On endpoint fails to check if a provider is restricted to account linking only. This allows an attacker with control over a linked upstream identity to bypass login restrictions and gain full access to a local user account.

EPSS: 0.002 (10.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16442?
CVE-2026-16442 is a high-severity vulnerability in Red Hat Build Of Keycloak, classified under Origin Validation Error. CVSS score: 7.4/10. Published 2026-08-05.
How severe is CVE-2026-16442?
High severity. CVSS v3 base score is 7.4 out of 10.