CVE-2026-16443highCWE-347

CVE-2026-16443: high-severity vulnerability in Red Hat build of Keycloak 26.4

Keycloak-services: keycloak-services: saml broker metadata import disables response signature validation

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.4epss 0.3%
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.14Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.5Red Hat · Red Hat Data Grid 8Red Hat · Red Hat JBoss Enterprise Application Platform Expansion PackRed Hat · Red Hat Single Sign-On 7
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