CVE-2026-33934 OpenEMR's Missing Authorization in show-signature.php Allows Portal Patients to Read Staff Signatures

Medium 4.3 Published 25 Mar 2026 Updated 26 Mar 2026

Authenticated patients can read any staff member's signature image due to missing authorization checks in the signature display endpoint.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-33934?

CVE-2026-33934 is a medium-severity missing authorization vulnerability in Open-Emr Openemr, published on 25 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

OpenEMR is a free and open source electronic health records and medical practice management application. Versions prior to 8.0.0.3 have a missing authorization check in `portal/sign/lib/show-signature.php` that allows any authenticated patient portal user to retrieve the drawn signature image of any staff member by supplying an arbitrary `user` value in the POST body. The companion write endpoint (`save-signature.php`) was already hardened against this same issue, but the read endpoint was not updated to match. Version 8.0.0.3 patches the issue.

Weakness: CWE-862, CWE-639

Which versions are affected by CVE-2026-33934?

It affects 1 product.

Products include Open-Emr Openemr.

How do I fix CVE-2026-33934?

No fix has been published for CVE-2026-33934 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-33934 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33934 exists.

All Open-Emr Openemr vulnerabilities

Sources

Also known as GHSA-w9w5-7x6h-657q.