CVE-2026-1486 is a vulnerability in the Red Hat Build of Keycloak, specifically in the jwt-authorization-grant flow, where the server fails to verify whether an Identity Provider (IdP) is enabled before issuing tokens. The function lookupIdentityProviderFromIssuer retrieves the IdP configuration based on the issuer but does not filter out IdPs marked as disabled (isEnabled=false). Consequently, if an administrator disables an IdP—commonly done to revoke trust due to compromise or offboarding—the system still accepts JWT assertions signed by that IdP's signing key. An attacker possessing the signing key of a disabled IdP can generate valid JWT tokens that Keycloak will accept, leading to unauthorized issuance of access tokens. This undermines the trust model of the federated identity system, allowing attackers to impersonate users or services associated with the disabled IdP. The vulnerability has a CVSS 3.1 score of 8.8, indicating high severity, with network attack vector, low attack complexity, requiring privileges but no user interaction, and impacting confidentiality, integrity, and availability. No known exploits are currently reported in the wild. The flaw affects environments where multiple IdPs are configured and managed via Keycloak, especially in enterprise or cloud deployments relying on Red Hat's build of Keycloak for identity federation and access control.

For European organizations, this vulnerability poses a significant risk to the security of identity and access management systems. Unauthorized token issuance can lead to privilege escalation, unauthorized access to sensitive data, and potential lateral movement within networks. Organizations relying on Keycloak for single sign-on (SSO) and federated identity management may experience breaches of confidentiality and integrity, undermining compliance with GDPR and other data protection regulations. The availability of services could also be impacted if attackers leverage the vulnerability to disrupt authentication flows or perform denial-of-service attacks. Given the widespread use of Red Hat products and Keycloak in European public and private sectors, especially in regulated industries such as finance, healthcare, and government, the potential impact is substantial. Attackers exploiting this flaw could bypass administrative controls intended to disable compromised or decommissioned IdPs, making incident response and remediation more complex.

Organizations should prioritize applying official patches from Red Hat as soon as they become available. In the interim, administrators must audit all configured IdPs in Keycloak to verify their enabled status and ensure that signing keys for disabled IdPs are securely revoked and rotated. Implement strict key management policies to prevent unauthorized access to IdP signing keys. Consider deploying additional monitoring and anomaly detection on token issuance logs to detect suspicious JWT assertions originating from disabled IdPs. Restrict administrative privileges to minimize the risk of insider threats and accidental misconfiguration. Where possible, implement compensating controls such as network segmentation and multi-factor authentication to reduce the impact of compromised tokens. Finally, review and update incident response plans to include scenarios involving compromised federated identity providers.