XSS in Openemr
CVE-2026-40507
OpenEMR before 8.3.0 contains a reflected cross-site scripting vulnerability in the patient portal template import handler. The templateHtml GET parameter is reflected into the page response without sanitization. An attacker can craft a URL that executes arbitrary JavaScript in the browser of any authenticated user with Forms Administration permissions who visits the link, enabling session hijacking.
Vulnerability class: XSS (Cross-Site Scripting)
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
Affected products
Weakness classification (CWE)
References
- disclosure@vulncheck.com (vendor-advisory)
- disclosure@vulncheck.com (release-notes)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-40507?
- CVE-2026-40507 is a medium-severity vulnerability in Openemr, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-08-19.
- How severe is CVE-2026-40507?
- Medium severity. CVSS v3 base score is 6.1 out of 10.