# CVE-2026-124466: OpenEMR server-side request forgery in OAuth2 jwks_uri

Source: https://junglewise.ai/threats/cve-2026-124466-openemr-before-8-4-0-contains-a-server-side-request-forgery  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-08. Updated: 2026-11-08  
License: CC BY 4.0 with a link back

CVE-2026-124466 · Severity: high · CVSS 7.2 · Published 2026-11-08

OpenEMR is a medical practice management and electronic health record system. An unauthenticated attacker can make the server send HTTP requests to any URL, including internal services and cloud metadata endpoints, by registering a malicious OAuth2 client and triggering a token introspection call. This allows probing of internal networks and potential credential theft from cloud environments without requiring any user account or interaction.

Technologies: [OpenEMR](https://junglewise.ai/threats/technologies/openemr-openemr). Vendors: [OpenEMR](https://junglewise.ai/threats/vendors/openemr).

## Quick answers

**Is CVE-2026-124466 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-124466 being exploited in the wild.

**How severe is CVE-2026-124466?** High severity, with a CVSS score of 7.2, published 8 November 2026.

**Which products and versions are affected?** OpenEMR before 8.4.0.

**Is there a fix for CVE-2026-124466?** Yes: fixed in 8.4.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-124466 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-124466?** Check whether you run OpenEMR at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in 8.4.0

## Technical details

The vulnerability is a server-side request forgery in OpenEMR's OAuth2 implementation. An attacker registers an OAuth2 client with an attacker-controlled jwks_uri without scheme or IP validation, then triggers a fetch via the token introspection endpoint with an unsigned client_assertion. The HTTP client fetches the jwks_uri before signature validation, enabling blind SSRF to internal addresses. Exploitation requires only that any API (REST, FHIR, or portal) is enabled, which is standard for most deployments.

## Affected products

- OpenEMR OpenEMR before 8.4.0

## Timeline

- 2026-09-13: disclosed
- 2026-11-08: advisory

## References

- [https://github.com/openemr/openemr/security/advisories/GHSA-mf6h-xc62-9fg4](https://github.com/openemr/openemr/security/advisories/GHSA-mf6h-xc62-9fg4)
- [https://www.vulncheck.com/advisories/openemr-before-8.4.0-unauthenticated-ssrf-via-oauth2-client-jwks-uri](https://www.vulncheck.com/advisories/openemr-before-8.4.0-unauthenticated-ssrf-via-oauth2-client-jwks-uri)

## Related threats

- [OpenEMR path traversal in oe-module-faxsms disposeDocument](https://junglewise.ai/threats/cve-2026-124490-openemr-before-8-3-0-contains-a-path-traversal-vulnerability-in)
- [OpenEMR broken access control in portal payment processing](https://junglewise.ai/threats/cve-2026-124489-openemr-before-8-3-0-contains-a-broken-access-control)
- [OpenEMR authorization bypass in encounter form loaders](https://junglewise.ai/threats/cve-2026-124488-openemr-before-8-3-0-contains-an-authorization-bypass)
- [OpenEMR improper authorization in FHIR DocumentReference $docref](https://junglewise.ai/threats/cve-2026-124487-openemr-before-8-4-0-contains-an-improper-authorization)
- [OpenEMR missing authorization in classic document controller](https://junglewise.ai/threats/cve-2026-124486-openemr-before-8-3-0-contains-a-missing-authorization)