CVE-2026-16443 Keycloak-services: keycloak-services: saml broker metadata import disables response signature validation
An unauthenticated attacker can forge SAML responses to gain unauthorized access to user accounts due to disabled signature validation during metadata import.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-16443?
CVE-2026-16443 is a high-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-347
Which versions are affected by CVE-2026-16443?
1 open source package ship an affected version, including keycloak. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
keycloak Bitnami | From 26.4.0 | 26.4.14, 26.6.5 |
Products include Redhat Build of Keycloak.
How do I fix CVE-2026-16443?
Upgrade keycloak to a fixed version for your release line: 26.4.14 or 26.6.5.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-16443 being exploited?
There is no known exploitation of CVE-2026-16443 in the wild and no public exploit code.
Other vulnerabilities in Redhat Build of Keycloak
- CVE-2026-15572 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation
- CVE-2026-3047 Keycloak SAML Broken has Authentication Bypass by Primary Weakness
- CVE-2026-15573 Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher
- CVE-2026-16102 Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers
- CVE-2026-1609 Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
Sources
Also known as BIT-keycloak-2026-16443, GHSA-v5j7-jp89-37vr.