Vulnerability · Published Mar 25, 2026 · Assigned by GitHub_M
CVE-2026-33934OpenEMR's Missing Authorization in show-signature.php Allows Portal Patients to Read Staff Signatures
Medium 4.3
In plain English
A medium-severity authorization bypass via user-controlled key in openemr from openemr. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities).
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.
Affected products (as reported)
Weakness: CWE-639, CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
References
- https://github.com/openemr/openemr/security/advisories/GHSA-w9w5-7x6h-657q x_refsource_CONFIRM
- https://github.com/openemr/openemr/commit/ae7ee1872d2e6300b165e24687cc90cf6847a4e5 x_refsource_MISC
- https://github.com/openemr/openemr/releases/tag/v8_0_0_3 x_refsource_MISC