Vulnerability in Freerdp
CVE-2026-67294
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 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.
Vulnerability class: Improper Certificate Validation
EPSS: 0.003 (18.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Freerdp — versions 0, 3.29.0
Weakness classification (CWE)
References
- disclosure@vulncheck.com (Exploit, vendor-advisory, Vendor Advisory)
- disclosure@vulncheck.com (Patch, patch)
- disclosure@vulncheck.com (Patch, Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-67294?
- CVE-2026-67294 is a medium-severity vulnerability in Freerdp, classified under Improper Certificate Validation. CVSS score: 5.9/10. Published 2026-08-01.
- How severe is CVE-2026-67294?
- Medium severity. CVSS v3 base score is 5.9 out of 10.