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.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:50846	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:50847	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:50848	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:50849	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-16442	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2503138	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:redhat:build_of_keycloak::::::::
	cpe:2.3:a:redhat:build_of_keycloak::::::::

History

No history.

Information

Published : 2026-08-05 16:16

Updated : 2026-08-10 19:21

NVD link : CVE-2026-16442

Mitre link : CVE-2026-16442

CVE.ORG link : CVE-2026-16442

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-346

Origin Validation Error

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