XSS in Open-Emr Openemr

CVE-2026-33911

OpenEMR is a free and open source electronic health records and medical practice management application. Prior to version 8.0.0.3, the POST parameter `title` is reflected back in a JSON response built with `json_encode()`. Because the response is served with a `text/html` Content-Type, the browser interprets injected HTML/script tags rather than treating the output as JSON. An authenticated attacker can craft a request that executes arbitrary JavaScript in a victim's session. Version 8.0.0.3 contains a fix.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (19.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 19.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-33911: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33911?
CVE-2026-33911 is a medium-severity vulnerability in Open-Emr Openemr, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-03-25.
How severe is CVE-2026-33911?
Medium severity. CVSS v3 base score is 5.4 out of 10.