CVE-2026-126473

EUVD-2026-124951
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
9.1 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 40.46%
Common Weakness Enumeration
References
https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4
https://www.vulncheck.com/advisories/openemr-before-8.4.0-oauth-authorization-bypass-via-scope-canonicalization
https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4