CVE-2026-33348
Published: 25 March 2026
Summary
CVE-2026-33348 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Open-Emr Openemr. Its CVSS base score is 8.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 8.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-15 (Information Output Filtering).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly addresses the vulnerability by requiring identification, reporting, and correction of the specific stored XSS flaw via patching to version 8.0.0.3.
Mandates validation of Eye Exam form inputs to reject malicious JavaScript payloads before storage, preventing injection by authenticated users with the 'Notes - my encounters' role.
Requires filtering of form answers prior to display on encounter pages and visit history, blocking execution of injected scripts in viewers' browsers.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Stored XSS in OpenEMR web app directly enables exploitation of public-facing application (T1190) via unsanitized form input, arbitrary JavaScript execution in victim browsers (T1059.007), and theft of web session cookies for account impersonation (T1539).
NVD Description
OpenEMR is a free and open source electronic health records and medical practice management application. Users with the `Notes - my encounters` role can fill Eye Exam forms in patient encounters. The answers to the form are displayed on the…
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encounter page and in the visit history for the users with the same role. Versions prior to 8.0.0.3 have a stored cross-site scripting (XSS) vulnerability in the function to display the form answers, allowing any authenticated attacker with the specific role to insert arbitrary JavaScript into the system by entering malicious payloads to the form answers. The JavaScript code is later executed by any user with the form role when viewing the form answers in the patient encounter pages or visit history. Version 8.0.0.3 contains a patch.
Deeper analysisAI
CVE-2026-33348 is a stored cross-site scripting (XSS) vulnerability, classified under CWE-79, affecting OpenEMR, a free and open-source electronic health records and medical practice management application. The flaw resides in the function responsible for displaying answers from Eye Exam forms within patient encounters. Users with the "Notes - my encounters" role can submit form answers that are then shown on the encounter page and in visit history for others with the same role. Versions of OpenEMR prior to 8.0.0.3 fail to properly sanitize these inputs, enabling the injection of arbitrary JavaScript payloads. The vulnerability carries a CVSS v3.1 base score of 8.7 (AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N), reflecting high confidentiality and integrity impacts due to its cross-origin scope change.
An authenticated attacker possessing the "Notes - my encounters" role can exploit this by entering malicious JavaScript into Eye Exam form fields during a patient encounter. When any other user with the same role views the affected encounter page or visit history, the injected code executes in their browser context. This allows the attacker to steal session cookies, manipulate page content, perform actions on behalf of the victim, or exfiltrate sensitive patient data visible to that role, all over the network with low complexity but requiring user interaction to trigger.
Mitigation is available via the official patch in OpenEMR version 8.0.0.3, as detailed in the project's GitHub security advisory (GHSA-6ch2-p26g-x33h), release notes, and the fixing commit (f488efbe3eb7f17d0f057f960020cb611149f8a2). Security practitioners should prioritize upgrading affected instances, validate input sanitization in custom forms, and enforce principle of least privilege for the "Notes - my encounters" role to limit exposure.
Details
- CWE(s)