Medplum

Medplum is a developer platform that enables development of healthcare apps. Prior to version 5.1.6, the external identity provider callback at GET /auth/external accepts attacker-controlled redirect URIs that only need to start with a registered client redirect URI, rather than matching exactly. After a successful external IdP login, the server appends Medplum login and code values to that attacker-supplied URL and issues a redirect. Because the external login request state is serialized as raw JSON and later trusted by the callback, an attacker who can tamper with state.redirectUri can cause Medplum to redirect authorization artifacts to an attacker-controlled endpoint. When the registered redirect URI is a bare origin or another prefix that can be extended into a different hostname, this becomes a cross-origin authorization code leak. This issue has been patched in version 5.1.6.

Published: 2026-09-03T19:04:30.358Z
Updated: 2026-09-09T17:40:52.953Z

Medplum before 5.1.14 contains a server-side request forgery vulnerability in the subscription worker that allows authenticated users to perform unauthorized internal network requests by creating FHIR Subscription resources with arbitrary endpoint URLs. Attackers can point subscription endpoints at internal addresses such as cloud instance metadata services, internal databases, or container orchestration endpoints to exfiltrate IAM credentials and patient health records via the POST body containing full FHIR resource payloads.

Published: 2026-06-02T18:05:09.825Z
Updated: 2026-11-08T14:04:40.597Z