Cyber Resilience

CVE-2026-33346

XSS in Open-Emr Openemr ≤ 8.0.0.2

Public PoCXSS
Published
19 March 2026
Modified
20 March 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
EPSS Score 0.0032 25th percentile
Risk Priority 59 floored blend · peak EPSS

Summary

CVE-2026-33346 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 Browser Session Hijacking (T1185); ranked at the 25th 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 map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-33346 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. Versions prior to 8.0.0.2 are vulnerable in the patient portal payment flow, where arbitrary JavaScript payloads submitted by users are stored via portal/lib/paylib.php and rendered without proper escaping in portal/portal_payment.php. The issue 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), indicating high severity due to its potential for significant confidentiality and integrity impacts.

An authenticated patient portal user with low privileges (PR:L) can exploit this vulnerability over the network (AV:N) by injecting malicious JavaScript during payment submission. The payload persists in storage and executes in the browser of a staff member (UI:R) who later reviews the payment details in portal/portal_payment.php, with low attack complexity (AC:L). Successful exploitation enables theft of sensitive data or manipulation of staff actions in the victim's session, achieving high confidentiality and integrity impacts (C:H/I:H) across a changed scope (S:C) without affecting availability.

OpenEMR version 8.0.0.2 addresses the vulnerability through a fix detailed in the commit at https://github.com/openemr/openemr/commit/6e9e1566d6e271a6d839614674b887e3a73d7da1. Additional mitigation guidance is available in the GitHub Security Advisory at https://github.com/openemr/openemr/security/advisories/GHSA-qvf6-6xc6-9qv7. Security practitioners should prioritize upgrading affected instances and reviewing patient portal configurations for exposure.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

OpenEMR is a free and open source electronic health records and medical practice management application. Prior to 8.0.0.2, a stored cross-site scripting (XSS) vulnerability in the patient portal payment flow allows a patient portal user to persist arbitrary JavaScript that…

more

executes in the browser of a staff member who reviews the payment submission. The payload is stored via `portal/lib/paylib.php` and rendered without escaping in `portal/portal_payment.php`. Version 8.0.0.2 fixes the issue.

CWE(s)
CWE-79

Related Threats

MITRE ATT&CK Enterprise Techniques

T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
attack.mitre.org →
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
attack.mitre.org →
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
attack.mitre.org →
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-2947Same product: Open-Emr Openemr
CVE-2022-2733Same product: Open-Emr Openemr
CVE-2023-2949Same product: Open-Emr Openemr
CVE-2023-2948Same product: Open-Emr Openemr
CVE-2023-22972Same product: Open-Emr Openemr
CVE-2023-2566Same product: Open-Emr Openemr
CVE-2020-13564Same product: Open-Emr Openemr
CVE-2020-13563Same product: Open-Emr Openemr
CVE-2020-13562Same product: Open-Emr Openemr
CVE-2023-25837Shared CWE-79

Affected Assets

open-emr
openemr
≤ 8.0.0.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.1.2
  • V1.3.2

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.

SI-10 Information Input Validation good match

Input validation directly enforces neutralization of untrusted data before it reaches web output generation.

SI-15 Information Output Filtering good match

Output filtering can catch or sanitize unneutralized script content before it is served to users.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).

PR.PS-02 partial match
prevents

Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.

A.5.6 Contact with special interest groups partial match
prevents

Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.

A.5.7 Threat intelligence partial match
prevents

Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.

A.8.25 Secure development life cycle partial match
prevents

Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.

A.8.28 Secure coding partial match
prevents

Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.

A.8.7 Protection against malware none match
none

Webpage malware scanning and block-listing of known malicious sites reduce the likelihood that reflected or stored script payloads reach a user’s browser.

References