CVE-2026-67294
critical · 9.3FreeRDP 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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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
Weaknesses
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| freerdp | freerdp | < 3.29.0 |
Check a specific version with /api/v1/cve/match.
References
- https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af319f
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4
- https://www.vulncheck.com/advisories/freerdp-before-tls-certificate-eku-bypass
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4
Query this programmatically:
curl https://evil-db.io/api/v1/cve/CVE-2026-67294