{"affected":[{"defaultStatus":"unaffected","product":"openemr","source":"CNA: VulnCheck","vendor":"openemr","versions":[{"lessThan":"8.4.0","status":"affected","version":"0","versionType":"semver"},{"status":"unaffected","version":"8.4.0","versionType":"semver"}]}],"cveId":"CVE-2026-126473","cwes":["CWE-863"],"description":"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.","epss":{"date":"2026-11-13","percentile":0.40455,"score":0.00461},"exploits":[{"kind":"exploit","source":"ADP: CISA-ADP","url":"https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4"}],"kev":null,"metrics":[{"score":9.3,"severity":"critical","source":"CNA: VulnCheck","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","version":"4.0"},{"score":9.1,"severity":"critical","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},{"score":9.3,"severity":"critical","source":"NVD: disclosure@vulncheck.com","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/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","version":"4.0"},{"score":9.1,"severity":"critical","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}],"modifiedAt":1794595287864,"publishedAt":1794562498505,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/openemr-before-8.4.0-oauth-authorization-bypass-via-scope-canonicalization"},{"source":"ADP: CISA-ADP","tags":["exploit"],"url":"https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/openemr/openemr/security/advisories/GHSA-6xh3-fmm5-jjp4"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/openemr-before-8.4.0-oauth-authorization-bypass-via-scope-canonicalization"}],"remediation":[],"revision":"0287966eceec742cfea51a302dab324c5771fbc0e52fd75acea9884c9dd408be","sources":[{"modifiedAt":1794595287864,"name":"CNA: VulnCheck","retrievedAt":1794597874307,"url":"https://www.cve.org/CVERecord?id=CVE-2026-126473"},{"modifiedAt":1794565076710,"name":"NVD","retrievedAt":1794572222164,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126473"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794597885856,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-126473"}],"ssvc":{"assessedAt":1794595258842,"automatable":"yes","exploitation":"poc","source":"ADP: CISA-ADP","technicalImpact":"total"},"status":"published","title":"OpenEMR before 8.4.0 OAuth Authorization Bypass via Scope Canonicalization","updatedAt":1794597885856}