openemr vulnerability

OpenEMR through 8.2.0 contains an improper authentication vulnerability in the OAuth2 dynamic client registration endpoint that allows unauthenticated attackers to register a malicious client with system-level FHIR scopes by supplying a self-generated RSA keypair via the jwks field. Once an administrator approves the registered client, attackers can use the client_credentials grant with a self-signed JWT assertion to obtain access tokens granting read access to all FHIR resources across all patients in the system.

Published 3 Aug 2026Updated 9 Sep 20262 sources
CVSS 8.6

What happened

OpenEMR through 8.2.0 contains an improper authentication vulnerability in the OAuth2 dynamic client registration endpoint that allows unauthenticated attackers to register a malicious client with system-level FHIR scopes by supplying a self-generated RSA keypair via the jwks field. Once an administrator approves the registered client, attackers can use the client_credentials grant with a self-signed JWT assertion to obtain access tokens granting read access to all FHIR resources across all patients in the system.

Affected versions

openemr: 0 through 8.2.0 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.