Missing Authorization in OpenEMR - #VU158858
Published: November 3, 2026
Vulnerability identifier: #VU158858
CSH Severity: Low
CVSS v4: 2.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-862
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to redeem previously issued authorization codes for access tokens after an administrator disables the OAuth2 client.
The vulnerability exists due to a missing client-enabled authorization check in CustomAuthCodeGrant::validateClient() when authenticating an authorization-code exchange using private_key_jwt. A remote user can submit an authorization code issued before client deactivation to /oauth2/default/token with a valid JWT client assertion for a client with a registered JWKS to obtain an access token despite the client being disabled.
Affected software
OpenEMR
Remediation
Install security update from vendor's website.
OpenEMR - update to 8.5.0