Improper Certificate Validation in FreeRDP - #VU156170
Published: October 19, 2026
Vulnerability details
The vulnerability allows a remote attacker to bypass server-identity verification and intercept or modify RDP session contents.
The vulnerability exists due to improper certificate validation in FreeRDP's TLS certificate identity checks when matching an IP-literal connection target against Common Name or DNS Subject Alternative Name strings instead of iPAddress Subject Alternative Names. A remote attacker can intercept or redirect an RDP connection and present a certificate that chains to a client-trusted CA, with a Common Name or DNS Subject Alternative Name equal to the target IP address but no corresponding iPAddress Subject Alternative Name, to bypass server-identity verification and read or manipulate session contents without a certificate warning.