Authorization Bypass

Keycloak is vulnerable to Authorization Bypass. The vulnerability is due to the token exchange feature ignoring tenant restrictions, where the restriction check is bypassed and an attacker with a valid Microsoft token from a different organization can gain access to the Keycloak realm...

CVE-2026-18215

Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization tenant. A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely...

CVE-2026-18215 Keycloak-services: keycloak-services: microsoft external access-token exchange bypasses configured tenant

Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization tenant. A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely...

CVE-2026-18215

Keycloak-security issue: Microsoft accounts login with tenant restriction can be bypassed via token exchange. A valid Microsoft token from a different organization could grant access to the Keycloak realm, exposing data or enabling unauthorized actions. Affected component is Keycloak’s Microsoft ...

CVE-2026-18215

Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization tenant. A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely...

User Impersonation

Overview Affected versions of this package are vulnerable to User Impersonation due to improper validation of JWT aud and iss claims in the Windows MDM authentication flow. An attacker can enroll unauthorized devices by presenting a valid Microsoft-signed Azure AD token from any tenant. This is...