CVE-2026-91949

Critical

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.

SeverityCritical

CVSS9.3

Exploit probability—

ProductFreerdp

PublishedSep 15, 2026

First seenSep 15, 2026

Weakness typeCWE-693CWE-693

How to fix

Update

freerdp freerdp3.31.0 or later

Vendor advisories

github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x7v6-xfx3-52j6

Affected products

Product	Affected versions	Fixed in
freerdp freerdp	3.0.0 ≤ v < 3.31.0	3.31.0

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