Reflected XSS via HTML-served JSON response
Published Mar 25, 2026 · Updated Mar 25, 2026
Reflected XSS in OpenEMR before 8.0.0.3 allows remote authenticated users to execute JavaScript in a victim's browser session. The graphs.php endpoint JSON-encodes the POST title value but serves the response as text/html, causing browsers to interpret injected tags as active content. Exploitation requires low-privileged authentication and victim interaction, and the resulting script runs in the victim's OpenEMR session within that user's browser context.
Summary
What happened
Reflected XSS in OpenEMR before 8.0.0.3 allows remote authenticated users to execute JavaScript in a victim's browser session. The graphs.php endpoint JSON-encodes the POST title value but serves the response as text/html, causing browsers to interpret injected tags as active content. Exploitation requires low-privileged authentication and victim interaction, and the resulting script runs in the victim's OpenEMR session within that user's browser context.
The record
- CVE
- CVE-2026-33911
- Published
- Mar 25, 2026
- Updated
- Mar 25, 2026
- Vendor
- OpenEMR Foundation
- Product
- OpenEMR
- Classifications
- CWE-79, T1203
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 25, 2026CVE publishedPublication date reported by the CVE source.
- Mar 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 8.0.0.3
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo