CVE-2026-109952

The FreeRDP client 3.0.0 before 3.32.0 does not check a server-selected PROTOCOL_RDSTLS or PROTOCOL_HYBRID_EX against its enabled protocol set in nego_process_negotiation_response(), allowing a security protocol downgrade. A malicious server or man-in-the-middle can select RDSTLS to override /sec:nla pinning, complete authentication with an all-zero cookie, and receive the user's cleartext password in the Client Info PDU.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-3.0.0-before-3.32.0-security-protocol-downgrade-via-negotiation-response	Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

History

21 Oct 2026, 14:16

Type	Values Removed	Values Added
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65 -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65 - Exploit, Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-3.0.0-before-3.32.0-security-protocol-downgrade-via-negotiation-response -~~	() https://www.vulncheck.com/advisories/freerdp-3.0.0-before-3.32.0-security-protocol-downgrade-via-negotiation-response - Third Party Advisory
CPE		cpe:2.3:a:freerdp:freerdp::::::::
First Time		Freerdp Freerdp freerdp

16 Oct 2026, 22:17

Type	Values Removed	Values Added
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65 -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65 -

13 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 14:17

Updated : 2026-10-21 14:16

NVD link : CVE-2026-109952

Mitre link : CVE-2026-109952

CVE.ORG link : CVE-2026-109952

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-757

Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')

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