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).

Severity (CVSS 3.1)4.3Medium
Exploit odds (30 days)0.2%top 84.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

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)

VendorProductVersions
openemr openemr < 8.0.0.3

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