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CVE coverage

CVE-2026-91949

CVSS 9.3 no coverage
View on NVD →
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.

Detection rules

No detection found — yet
None of Sigma, Elastic, Splunk ESCU, YARA, Microsoft Sentinel, Snort, or Suricata currently has a rule referencing CVE-2026-91949.