Threats Tagged 'cve-2026-37977'

Red Hat build of Keycloak is an integrated sign-on solution, available as a Red Hat JBoss Middleware for OpenShift containerized image. The Red Hat build of Keycloak for OpenShift image provides an authentication server that you can use to log in centrally, log out, and register. You can also manage user accounts for web applications, mobile applications, and RESTful web services. Red Hat build of Keycloak Operator for OpenShift simplifies deployment and management of Keycloak 26.4.13 clusters. This erratum releases new images for Red Hat build of Keycloak 26.4.13 for use within the OpenShift Container Platform cloud computing Platform-as-a-Service (PaaS) for on-premise or private cloud deployments, aligning with the standalone product release. Security fixes: * Information disclosure via CORS header injection due to unvalidated JWT azp claim (CVE-2026-37977) * Server-Side Request Forgery via OIDC token endpoint manipulation (CVE-2026-4874) * eclipse-vertx/vert.x:Denial of Service via TLS handshake with wildcard server name (CVE-2026-6860) * Improper Access Control on Keycloak Server when the account Account API feature is disabled (CVE-2026-7500) * Policy bypass during WebAuthn credential registration via client-side JavaScript manipulation (CVE-2026-8830) * Security flaw in org.keycloak/keycloak-services (CVE-2026-8922) * Information disclosure through arbitrary filesystem path probing (CVE-2026-9083) * Cross-site scripting (XSS) via case-insensitive URI validation bypass (CVE-2026-9086) * Cross-Session Email Verification Proof Not Bound to Upstream Identity in First-Broker-Login (CVE-2026-9087) * Information disclosure due to user profile permission bypass (CVE-2026-9088) * Group-Admin Escalation to Realm-Admin (CVE-2026-9099) * Privilege escalation due to oversized subject_token JWT (CVE-2026-9704) * Attacker can re-enable and take over disabled clients via Registration Access Token (CVE-2026-9705) * Organization Data Leak After Feature Disabled in Keycloak (CVE-2026-9791) * Security restriction bypass allows unauthorized ROPC token acquisition (CVE-2026-9792) * Information disclosure via SAML ECP endpoint (CVE-2026-9794) * Privilege escalation via improper scope mapping enforcement (CVE-2026-9795) * Unauthorized access to resources via UMA permission ticket bypass (CVE-2026-9799) * Authorization bypass via incorrect URI comparison (CVE-2026-9800) * Denial of Service via malformed LDAP password policy response (CVE-2026-9801) * Unauthorized account access via replayed refresh tokens after cluster restart (CVE-2026-9802) * Denial of Service via malformed Authorization header (CVE-2026-9803)

A flaw was found in Keycloak. A remote attacker can exploit a Cross-Origin Resource Sharing (CORS) header injection vulnerability in Keycloak's User-Managed Access (UMA) token endpoint. This flaw occurs because the `azp` claim from a client-supplied JSON Web Token (JWT) is used to set the `Access-Control-Allow-Origin` header before the JWT signature is validated. When a specially crafted JWT with an attacker-controlled `azp` value is processed, this value is reflected as the CORS origin, even if the grant is later rejected. This can lead to the exposure of low-sensitivity information from authorization server error responses, weakening origin isolation, but only when a target client is misconfigured with `webOrigins: ["*"]`.