Improper Authentication in OpenEMR OAuth2 Client Registration by OpenEMR
CVE-2026-67610

8.6HIGH

Key Information:

Vendor

Openemr

Status
Openemr
Vendor
CVE Published:
3 August 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-67610?

OpenEMR versions up to 8.2.0 are susceptible to an improper authentication vulnerability in the OAuth2 dynamic client registration endpoint. This flaw allows unauthenticated attackers to register a malicious client by submitting a self-generated RSA keypair through the jwks field. Once an administrator approves this registered client, the attackers can exploit the client_credentials grant in conjunction with a self-signed JWT assertion, enabling them to acquire access tokens. These tokens allow read access to all FHIR resources, potentially compromising the confidentiality of all patients' data within the system.

Affected Version(s)

openemr 0 <= 8.2.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-67610 - Proof of Concept

References

https://jivasecurity.com/writeups/openemr-unauth-oauth2-c...
technical-descriptionexploit
https://www.vulncheck.com/advisories/openemr-oauth2-dynam...
third-party-advisory

CVSS V4

Score:
8.6
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Jiva (JivaSecurity)
.