VU#889462: Casdoor authentication server is vulnerable to authorization bypass

Casdoor is an open-source Access Management (IAM) platform used to manage web applications. An authorization bypass vulnerability affects Casdoor versions up to v4.2.0. The vulnerability allows a non-global organization administrator to perform unauthorized administrative actions against arbitrary organizations by exploiting inconsistent object resolution between the authorization layer and downstream controllers. In multi-tenant deployments, an attacker with administrative privileges within a single organization can bypass tenant isolation and perform administrative operations against other organizations.

CVE-2026-15630.
The vulnerability stems from a desynchronization between authorization and action in multiple POST /api/{add,delete}- endpoints (e.g., /api/add-user, /api/delete-user, /api/add-permission). While the global authorization filter (routers/authzfilter.go) correctly uses the ?id= URL query parameter as the authoritative target for authorization decisions, the affected controllers (controllers/user.go, controllers/permission.go, etc.) ignore ?id= and operate solely on the owner and name fields in the JSON request body. As a result, authorization is evaluated against one object while the requested operation is executed against another, allowing an authenticated organization administrator (IsAdmin=true) to perform unauthorized administrative actions across tenant boundaries.

An attacker with administrative privileges in a single organization can compromise the isolation guarantees of a multi-tenant Casdoor deployment. Depending on the exposed endpoints and deployment configuration, successful exploitation can allow for administrative operations including user management, privilege management and disruption of single sign-on (SSO) or Security Assertion Markup Language (SAML) identity. The overall impact can escalate to a complete compromise of tenant isolation and, in some deployment scenarios, potential compromise of the entire Casdoor instance.