{"affected":[{"defaultStatus":"unaffected","product":"openemr","source":"CNA: VulnCheck","vendor":"openemr","versions":[{"lessThan":"8.5.0","status":"affected","version":"0","versionType":"semver"},{"status":"unaffected","version":"8.5.0","versionType":"semver"}]}],"cveId":"CVE-2026-126436","cwes":["CWE-862"],"description":"OpenEMR before 8.5.0 contains an authorization bypass vulnerability that allows OAuth2 clients to use unregistered grant types because oauth_clients.grant_types is never enforced. Attackers can request tokens with grant_type=password to bypass the user consent screen, and disabled clients can redeem authorization codes using JWT client assertions.","epss":{"date":"2026-11-13","percentile":0.3823,"score":0.00434},"exploits":[],"kev":null,"metrics":[{"score":8.7,"severity":"high","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","version":"4.0"},{"score":7.5,"severity":"high","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"},{"score":8.7,"severity":"high","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/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":7.5,"severity":"high","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"}],"modifiedAt":1794600521946,"publishedAt":1794562522891,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/openemr/openemr/security/advisories/GHSA-qjj7-c4m9-6f92"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/openemr-before-8.5.0-oauth2-grant-type-enforcement-bypass-via-token-endpoint"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/openemr/openemr/security/advisories/GHSA-qjj7-c4m9-6f92"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/openemr-before-8.5.0-oauth2-grant-type-enforcement-bypass-via-token-endpoint"}],"remediation":[],"revision":"f7c848861fa15cf1feb916b38d04196cd5c5cb450f8b1b039abecf9e0750083f","sources":[{"modifiedAt":1794600521946,"name":"CNA: VulnCheck","retrievedAt":1794604195470,"url":"https://www.cve.org/CVERecord?id=CVE-2026-126436"},{"modifiedAt":1794565070620,"name":"NVD","retrievedAt":1794572215460,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126436"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794604221051,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-126436"}],"ssvc":{"assessedAt":1794600505304,"automatable":"yes","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"OpenEMR before 8.5.0 OAuth2 Grant Type Enforcement Bypass via Token Endpoint","updatedAt":1794604221051}