CVE-2026-2603

Keycloak: keycloak: unauthorized authentication via disabled saml identity provider

Published: Mar 18, 2026Updated: Aug 18, 2026 Sources: CVE List NVDCWE-306

8.1HIGH

Description

A flaw was found in Keycloak. A remote attacker could bypass security controls by sending a valid SAML response from an external Identity Provider (IdP) to the Keycloak SAML endpoint for IdP-initiated broker logins. This allows the attacker to complete broker logins even when the SAML Identity Provider is disabled, leading to unauthorized authentication.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:NAvailability

None

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Weaknesses

CWE-306

Affected Products

Red Hat

commercial·USaka redhat

build of keycloakOn-prem

Operating Systems / linux-distro

Red Hat build of Keycloak 26.2On-prem

Operating Systems / linux-distro

Red Hat build of Keycloak 26.2.14On-prem

OSS Libraries / generic-library

Red Hat build of Keycloak 26.4On-premWeb App

Web & CMS Plugins

Red Hat build of Keycloak 26.4.10On-premWeb App

Security Products / identity-access-mgmt

Exploitability

Official Patch Available

Workaround Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

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References

https://access.redhat.com/errata/RHSA-2026:3925

access.redhat.com

https://access.redhat.com/errata/RHSA-2026:3926

access.redhat.com

https://access.redhat.com/errata/RHSA-2026:3947

access.redhat.com

and 4 more references View all →

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