CVE-2026-33303Public exploitNetwork attack vector

Staff-session script execution via unescaped portal username

Published Mar 19, 2026 · Updated Mar 19, 2026

Stored XSS in OpenEMR before 8.0.0.2 allows remote authenticated users to execute JavaScript in a clinic staff browser. The credential print Twig template inserts the stored portal username into an HTML value attribute without attribute escaping while autoescaping is disabled. Exploitation requires a patient portal account and current password, followed by staff opening that patient's Create Portal Login page; the script can read staff-visible content and submit forms as that staff user.

CVSS severity5.4
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in OpenEMR before 8.0.0.2 allows remote authenticated users to execute JavaScript in a clinic staff browser. The credential print Twig template inserts the stored portal username into an HTML value attribute without attribute escaping while autoescaping is disabled. Exploitation requires a patient portal account and current password, followed by staff opening that patient's Create Portal Login page; the script can read staff-visible content and submit forms as that staff user.

The record

CVE
CVE-2026-33303
Published
Mar 19, 2026
Updated
Mar 19, 2026
Vendor
OpenEMR Foundation
Product
OpenEMR
Classifications
CWE-79, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 8.0.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OpenEMR Foundation · OpenEMRversion=< 8.0.0.2

Published CVSS scores

5.4GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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