CVE-2026-126473 PUBLISHED

OpenEMR before 8.4.0 OAuth Authorization Bypass via Scope Canonicalization

Assigner: VulnCheck
Reserved: 10.11.2026 Published: 13.11.2026 Updated: 13.11.2026

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.

CVSS Vector: 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
CVSS Score: 9.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	None	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS Score: 9.1

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	openemr
Product	openemr
Versions	Default: unaffected affected from 0 to 8.4.0 (excl.) Version 8.4.0 is unaffected

CVE-2026-126473 PUBLISHED

OpenEMR before 8.4.0 OAuth Authorization Bypass via Scope Canonicalization

Metrics

Product Status

Credits

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Problem Types