CVE-2026-91949
CRITICAL
NVD
CVSS Score
9.3
Severity
CRITICAL
Published
Sep 15, 2026
Vendor
unknown
Description
FreeRDP server versions before 3.31.0 contain a protocol negotiation bypass vulnerability that allows unauthenticated attackers to establish RDSTLS connections despite server policy disabling them. Attackers can send incompatible protocol requests, receive negotiation failures, then complete TLS handshake and enter RDSTLS to bypass pre-authentication transport restrictions.