CVE-2020-4033 : Security Advisory and Response

CVE-2020-4033 is an out-of-bounds read vulnerability in FreeRDP's RLEDECOMPRESS function affecting versions prior to 2.1.2.

Understanding CVE-2020-4033

In FreeRDP before version 2.1.2, an out-of-bounds read vulnerability in RLEDECOMPRESS was identified, impacting all FreeRDP clients with sessions having a color depth less than 32.

What is CVE-2020-4033?

The CVE-2020-4033 vulnerability involves an out-of-bounds read issue in the RLEDECOMPRESS function of FreeRDP, which could be exploited by an attacker to read data beyond the boundaries of an allocated memory buffer.

The Impact of CVE-2020-4033

The impact of this vulnerability is rated as low severity, with a CVSS base score of 3.1. Although the exploitation requires high attack complexity, it could lead to the disclosure of limited information.

Technical Details of CVE-2020-4033

Vulnerability Description

The vulnerability is classified as CWE-125: Out-of-bounds Read, indicating the issue of reading data beyond the allocated buffer boundaries.

Affected Systems and Versions

Vendor: FreeRDP
Product: FreeRDP
Versions Affected: < 2.1.2

Exploitation Mechanism

The vulnerability can be exploited by malicious actors to read data outside the bounds of the allocated memory buffer, potentially leading to information disclosure.

Mitigation and Prevention

Immediate Steps to Take

Users should update FreeRDP to version 2.1.2 or later to mitigate the vulnerability.
Implement network security measures to prevent unauthorized access to vulnerable systems.

Long-Term Security Practices

Regularly monitor security advisories and update systems promptly.
Conduct security assessments and audits to identify and address vulnerabilities proactively.

Patching and Updates

Apply patches and updates provided by FreeRDP to address the vulnerability and enhance system security.