Medium severity · published Aug 1, 2026
CVE-2026-67294
FreeRDP before 3.29.0 TLS Certificate EKU Bypass
5.9
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
before 3.29.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-67294
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-67294
Patch
https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af319f
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4
Patch
https://www.vulncheck.com/advisories/freerdp-before-tls-certificate-eku-bypass
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