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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af319f	Patch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-tls-certificate-eku-bypass	Patch Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-01 13:16

Updated : 2026-09-11 21:03

NVD link : CVE-2026-67294

Mitre link : CVE-2026-67294

CVE.ORG link : CVE-2026-67294

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-295

Improper Certificate Validation

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