FreeRDP up to 3.31.x Proxy http_proxy_connect msts injection

Summaryinfo

A vulnerability has been found in FreeRDP up to 3.31.x and classified as critical. Affected by this vulnerability is the function http_proxy_connect of the component Proxy. This manipulation of the argument msts causes injection. The identification of this vulnerability is CVE-2026-110835. It is possible to initiate the attack remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in FreeRDP up to 3.31.x. Affected by this vulnerability is the function http_proxy_connect of the component Proxy. The manipulation of the argument msts with an unknown input leads to a injection vulnerability. The CWE definition for the vulnerability is CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. As an impact it is known to affect integrity, and availability. The summary by CVE is:

FreeRDP 3.0.0 before 3.32.0 allows HTTP header injection in its proxy because a lone LF in the target portion of a routing token (Cookie: msts=) is not rejected and is written by http_proxy_connect into the CONNECT request line and Host header. A remote unauthenticated RDP client connecting to a proxy using FixedTarget=false and an upstream HTTP proxy can alter HTTP request/header framing at that upstream proxy.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-110835 since 10/15/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1055 for this issue.

Upgrading to version 3.32.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Remote Access Software

Name

• FreeRDP

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6
• 3.7
• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14
• 3.15
• 3.16
• 3.17
• 3.18
• 3.19
• 3.20
• 3.21
• 3.22
• 3.23
• 3.24
• 3.25
• 3.26
• 3.27
• 3.28
• 3.29
• 3.30
• 3.31

License

• open-source

Website

• Product: https://github.com/FreeRDP/FreeRDP/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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