Vulnerability · Published Aug 19, 2026 · Assigned by VulnCheck

CVE-2026-40508OpenEMR < 8.3.0 Stored XSS via Patient Portal Template Import Handler

Medium 5.4

In plain English

A medium-severity cross-site scripting in openemr from openemr. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities).

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.3%top 77.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

OpenEMR before 8.3.0 contains a stored cross-site scripting vulnerability in the patient portal template import handler that allows authenticated attackers with Forms Administration permissions to upload template files containing arbitrary HTML or JavaScript. Attackers can inject malicious scripts through the template upload functionality, which are stored without sanitization and execute in the browser of any other Forms Administration user who views the template in the HTML editor.

Affected products (as reported)

Vendor	Product	Versions
openemr	openemr	0 – before 8.3.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

References

GitHub Security Advisory (GHSA-5293-8q47-cf44) vendor-advisory
OpenEMR v8_3_0 Release Notes release-notes
Patch Commit patch
https://www.vulncheck.com/advisories/openemr-stored-xss-via-patient-portal-template-import-handler third-party-advisory