CVE-2023-39353 : Security Advisory and Response

Understanding CVE-2023-39353

A vulnerability in FreeRDP, a free implementation of the Remote Desktop Protocol (RDP), has been identified. The issue is related to a missing offset validation leading to an Out Of Bound Read.

What is CVE-2023-39353?

FreeRDP, known for its Apache licensed implementation of RDP, is impacted by a missing offset validation vulnerability. This flaw allows crafted input to trigger an out of bounds read access, potentially leading to a system crash.

The Impact of CVE-2023-39353

The vulnerability in FreeRDP's

libfreerdp/codec/rfx.c

file can result in unauthorized read access beyond the bounds of allocated memory, which could be exploited by attackers to disrupt systems and services.

Technical Details of CVE-2023-39353

The vulnerability has been assigned a CVSS v3.1 base score of 5.3, indicating a medium severity level with low attack complexity and network-based attack vectors.

Vulnerability Description

In FreeRDP versions prior to 2.11.0 and between 3.0.0-beta1 and 3.0.0-beta3, the missing offset validation in specific components allows malicious input to cause out of bounds read operations, potentially leading to crashes.

Affected Systems and Versions

The vulnerability affects FreeRDP versions < 2.11.0 and >= 3.0.0-beta1, < 3.0.0-beta3. Users of these versions are at risk of exploitation and are advised to update to patched versions.

Exploitation Mechanism

Attackers can leverage the absence of offset validation in certain variables to manipulate input data, triggering out of bounds read operations and compromising system integrity.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-39353, immediate steps should be taken alongside incorporating long-term security practices.

Immediate Steps to Take

Users should update FreeRDP to versions 2.11.0 or 3.0.0-beta3 to address the vulnerability and prevent potential exploits.

Long-Term Security Practices

Implement regular security updates and patches to keep systems protected against known vulnerabilities.
Conduct security audits and code reviews to identify and address potential weaknesses in software implementations.
Consider implementing network security measures to detect and prevent malicious activities targeting vulnerable software.

Patching and Updates

Stay informed about security advisories from FreeRDP and promptly apply patches or updates to ensure the continued security of your systems and data.