CVE-2026-40507

OpenEMR < 8.3.0 Reflected XSS via templateHtml Parameter in Patient Portal

MEDIUM
6.1
CVSS Score
Published: August 19, 2026 at 02:48 PM UTC
Updated: October 27, 2026 at 01:10 PM UTC
1 product affected across 1 vendorOpenEMR

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

OpenEMR before 8.3.0 contains a reflected cross-site scripting vulnerability in the patient portal template import handler. The templateHtml GET parameter is reflected into the page response without sanitization. An attacker can craft a URL that executes arbitrary JavaScript in the browser of any authenticated user with Forms Administration permissions who visits the link, enabling session hijacking.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 8.3.0
Affected range stops below 8.3.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.1MEDIUMVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-79

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