CVE-2026-126473 json
OpenEMR before 8.4.0 OAuth Authorization Bypass via Scope Canonicalization
published 18d ago modified yesterday also EUVD-2026-124951 , GHSA-6xh3-fmm5-jjp4
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository openemr/openemr. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
OpenEMR before 8.4.0 contains OAuth scope canonicalization and containment flaws that allow unauthenticated attackers to obtain unapproved system-level FHIR access. Attackers can register a colon-form system:Patient.read client that bypasses approval, then request unregistered system/Patient.write scope to read, modify, and create Patient records.
Patch / fix
- openemr openemr 8.4.0
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- total
- Assessed
- yesterday
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-14).
Exploits and checks
- github.com https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- openemr openemr
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4
vendor-advisory, exploit, advisory
-
vulncheck.com
/advisories/openemr-before-8.4.0-oauth-authorization-bypass-via-scope-canonicalization
third-party-advisory
Sources
- CVE List CVE-2026-126473
- NVD CVE-2026-126473
- Maintainer advisory GHSA-6xh3-fmm5-jjp4
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of openemr/openemr published their own advisory on GitHub. Reviewed sources take precedence over it.