CVE-2022-39318 : Security Advisory and Response

FreeRDP is a free remote desktop protocol library and clients. Affected versions of FreeRDP are missing input validation in the

urbdrc

channel, allowing a malicious server to trick a FreeRDP-based client to crash with division by zero. This vulnerability has been addressed in version 2.9.0. All users are advised to upgrade, with a caution for users unable to upgrade not to use the

/usb

redirection switch.

Understanding CVE-2022-39318

This section provides insights into the nature and impact of the CVE-2022-39318 vulnerability.

What is CVE-2022-39318?

CVE-2022-39318 is a vulnerability in FreeRDP where missing input validation in the

urbdrc

channel allows a malicious server to trigger a division by zero in FreeRDP-based clients.

The Impact of CVE-2022-39318

The impact of this vulnerability is the potential crashing of FreeRDP-based clients due to a division by zero, leading to a denial of service (DoS) condition.

Technical Details of CVE-2022-39318

This section delves into the technical aspects of CVE-2022-39318.

Vulnerability Description

The vulnerability arises from the lack of input validation in the

urbdrc

channel in affected versions of FreeRDP.

Affected Systems and Versions

The vulnerability affects FreeRDP versions prior to 2.9.0.

Exploitation Mechanism

A malicious server can exploit this vulnerability to crash FreeRDP-based clients by triggering a division by zero.

Mitigation and Prevention

This section outlines steps to mitigate and prevent attacks leveraging CVE-2022-39318.

Immediate Steps to Take

All users are strongly advised to upgrade to FreeRDP version 2.9.0 to address the vulnerability. Users unable to update should refrain from using the

/usb

redirection switch.

Long-Term Security Practices

Regularly updating software and implementing secure coding practices can help prevent similar vulnerabilities in the future.

Patching and Updates

Stay informed about security advisories and promptly apply patches released by FreeRDP to safeguard against known vulnerabilities.