CVE-2023-40186 Explained : Impact and Mitigation

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. This CVE involves an IntegerOverflow leading to an Out-Of-Bound Write Vulnerability in the

gdi_CreateSurface

function in FreeRDP. Discover more about the impact, technical details, and mitigation strategies below.

Understanding CVE-2023-40186

FreeRDP, an open-source RDP implementation, contains a critical vulnerability caused by an IntegerOverflow, potentially allowing an attacker to perform an Out-Of-Bound Write.

What is CVE-2023-40186?

The CVE-2023-40186 vulnerability in FreeRDP affects versions prior to 2.11.0 and >= 3.0.0-beta1, < 3.0.0-beta3. The flaw lies in the

gdi_CreateSurface

function, posing a risk to FreeRDP-based clients.

The Impact of CVE-2023-40186

This vulnerability could be exploited by remote attackers to execute arbitrary code or cause a denial of service (DoS) condition. However, FreeRDP proxies are not affected as they do not perform image decoding.

Technical Details of CVE-2023-40186

The CVE-2023-40186 vulnerability is assigned a CVSSv3.1 base score of 6.5, indicating a Medium severity issue. The attack complexity is low, with network access required.

Vulnerability Description

The CVE stems from an IntegerOverflow issue, leading to an Out-Of-Bound Write vulnerability within the

gdi_CreateSurface

function of FreeRDP.

Affected Systems and Versions

FreeRDP versions < 2.11.0 and >= 3.0.0-beta1, < 3.0.0-beta3 are impacted by this vulnerability. Users of FreeRDP-based clients are advised to take immediate action.

Exploitation Mechanism

Remote attackers can exploit this vulnerability to trigger an Out-Of-Bound Write, potentially resulting in arbitrary code execution or a DoS condition.

Mitigation and Prevention

It is crucial to apply the necessary mitigation steps to safeguard systems from CVE-2023-40186.

Immediate Steps to Take

Users are strongly advised to update FreeRDP to version 2.11.0 or 3.0.0-beta3 to address the IntegerOverflow leading to an Out-Of-Bound Write Vulnerability.

Long-Term Security Practices

Maintain a proactive approach to security by regularly updating software components and monitoring for security advisories related to FreeRDP.

Patching and Updates

Stay informed about security patches and updates released by FreeRDP to address vulnerabilities promptly.