---
id: "CVE-2026-126494"
page: "https://infrastack.ai/live/CVE-2026-126494"
kind: "vulnerability"
aliases: ["CVE-2026-126494"]
title: "OpenEMR: read-only OAuth clients can obtain write scopes and change patient data"
severity: "high"
cvss: 7.1
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["healthcare", "oauth", "openemr", "runtime", "self-hosted", "smart-on-fhir"]
not_affected_if: ["no-oauth-clients-registered", "openemr-8.4.0-or-later"]
published_at: "2026-11-13T10:18:00+00:00"
first_seen_at: "2026-11-13T10:47:27+00:00"
updated_at: "2026-11-13T10:52:55+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126494", "first_seen_at": "2026-11-13T10:47:27+00:00"}]
exploit_sources: []
---

# OpenEMR: read-only OAuth clients can obtain write scopes and change patient data

Link for people: https://infrastack.ai/live/CVE-2026-126494 (this .md is for agents)

OpenEMR before 8.4.0 fails to enforce a client's registered permissions when issuing OAuth scopes, so a read-only SMART client can request write scopes. An attacker with such a client can create, update, and delete appointments or patient records.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the OpenEMR version in the installation; versions before `8.4.0` are affected per the description
- Check whether SMART/OAuth client registration is enabled and whether any read-only clients are registered

## Fix

- OpenEMR: move to `8.4.0` or later (per the description, the fix is in 8.4.0)

## Timeline

- 2026-11-13T10:47:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126494

## Documents

- [advisory] Vendor advisory: github.com https://github.com/openemr/openemr/security/advisories/GHSA-6cmr-r2rh-755m
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/openemr-before-8.4.0-privilege-escalation-via-smart-oauth-scope-finalization

## From the sources

OpenEMR before 8.4.0 contains an improper authorization vulnerability in ScopeRepository::finalizeScopes() that allows read-only SMART/OAuth clients to obtain write scopes because ScopeEntity::containsScope() ignores registered permissions. Attackers with a client registered for user/<resource>.read can request user/<resource>.write to create, update, and delete appointments or patient data.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_