Description
A flaw was found in the SAML metadata import functionality of the keycloak-services component, which is the core engine for identity brokering in Red Hat Build of Keycloak. When importing identity provider metadata that lacks specific usage attributes for keys, the system incorrectly disables signature validation for SAML responses even if a signing certificate is provided. This issue allows an unauthenticated attacker to forge a SAML response and gain unauthorized access to a user account by knowing their external identifier.
Affected products
redhat: build of keycloak
References6
- access.redhat.com/errata/RHSA-2026:50846 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50847 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50848 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50849 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-16443 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2503139 Issue TrackingVendor Advisory
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 25 · as of 13 November 2026
- CWE
- CWE-347
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