{"id":"CVE-2026-67294","title":"FreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication","summary":"FreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication. In x509_utils_verify(), when server-purpose (X509_PURPOSE_SSL_SERVER) verification fail…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","cwe":["CWE-295"],"vendor":"freerdp","product":"freerdp","affected":["freerdp < 3.29.0"],"patched":["freerdp 3.29.0"],"published":"2026-08-01","updated":"2026-09-11","sourceUpdated":"2026-09-11T21:03:16.017","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-67294","references":[{"url":"https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af319f","label":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/freerdp-before-tls-certificate-eku-bypass","label":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00266,"epssPercentile":0.1873,"ingestedAt":"2026-08-02T05:17:49.550Z","slug":"CVE-2026-67294","body":"## Overview\n\nFreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication. In x509_utils_verify(), when server-purpose (X509_PURPOSE_SSL_SERVER) verification fails, the code falls back to client-purpose and any-purpose verification, so a trusted, hostname-matching certificate valid only for clientAuth can be accepted as the RDP server certificate. In environments relying on EKU separation between client and server certificates, this allows a clientAuth-only certificate issued by a trusted CA to bypass server certificate purpose validation.\n\n## Affected\n\n- `freerdp < 3.29.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `freerdp 3.29.0`","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}