CVE-2026-33934 (GCVE-0-2026-33934)

Vulnerability from cvelistv5 – Published: 2026-03-25 23:41 – Updated: 2026-03-26 18:09
VLAI
Title
OpenEMR's Missing Authorization in show-signature.php Allows Portal Patients to Read Staff Signatures
Summary
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.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-26 18:09 UTC
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
  • CWE-862 - Missing Authorization
Assigner
References
Impacted products
Vendor Product Version
openemr openemr Affected: < 8.0.0.3
Create a notification for this product.
Show details on NVD website
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