CVE-2026-67294
CRITICAL
9,3
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A
MEDIUM
5,9
Source: [email protected]
Attack Vector: network
Attack Complexity: high
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: none
Availability: none
Description
AI Translation Available
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.
295
Improper Certificate Validation
DraftCommon Consequences
Security Scopes Affected:
Integrity
Authentication
Potential Impacts:
Bypass Protection Mechanism
Gain Privileges Or Assume Identity
Applicable Platforms
Technologies:
Not Technology-Specific, Web Based, Mobile
https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af3…
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4
https://www.vulncheck.com/advisories/freerdp-before-tls-certificate-eku-bypass