CVE-2026-91949

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.

CVSS v3 9.3 CRITICAL

9.3^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x7v6-xfx3-52j6
https://www.vulncheck.com/advisories/freerdp-3.0.0-through-3.30.0-protocol-negotiation-bypass

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-15 16:17

NVD link : CVE-2026-91949

Mitre link : CVE-2026-91949

CVE.ORG link : CVE-2026-91949

JSON object : View

Products Affected

No product.

CWE

CWE-693

Protection Mechanism Failure

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