CVE-2026-1486

Description

A flaw was found in Keycloak. A vulnerability exists in the jwt-authorization-grant flow where the server fails to verify if an Identity Provider (IdP) is enabled before issuing tokens. The issuer lookup mechanism (lookupIdentityProviderFromIssuer) retrieves the IdP configuration but does not filter for isEnabled=false. If an administrator disables an IdP (e.g., due to a compromise or offboarding), an entity possessing that IdP's signing key can still generate valid JWT assertions that Keycloak accepts, resulting in the issuance of valid access tokens.

Statement

This vulnerability is rated Important for Red Hat products because Keycloak, when configured with JWT authorization grants, fails to verify the enabled status of an Identity Provider (IdP). An attacker possessing the IdP's signing key can issue valid access tokens even if the IdP has been administratively disabled, leading to unauthorized access.

Mitigation

To mitigate this issue, administrators should immediately revoke or rotate the signing keys associated with any Identity Provider that has been disabled in Keycloak. This operational control is crucial to prevent unauthorized token issuance by ensuring that compromised or offboarded IdP keys cannot be used to generate valid JWT assertions.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score8.8N/A8.8
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityHighN/AHigh
Integrity ImpactHighN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Access Control

Technical Impact: Bypass Protection Mechanism

Acknowledgements

Red Hat would like to thank Joy Gilbert Dan and Reynaldo Immanuel for reporting this issue.

Frequently Asked Questions

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