CVE-2023-4255 : What You Need to Know

This CVE record was published by Red Hat on December 21, 2023, and pertains to an out-of-bounds write vulnerability in the W3M application. The vulnerability was reported on July 19, 2023, and made public on June 12, 2023.

Understanding CVE-2023-4255

This section will delve into the details of CVE-2023-4255 and its impact, technical aspects, as well as mitigation strategies.

What is CVE-2023-4255?

CVE-2023-4255 is an out-of-bounds write vulnerability found in the backspace handling of the checkType() function in the etc.c file within the W3M application. Attackers can exploit this flaw by providing a specially crafted HTML file to the W3M binary, potentially leading to application crashes and denial of service.

The Impact of CVE-2023-4255

The impact of this vulnerability is rated as moderate with a CVSS base score of 5.5. While confidentiality and integrity impacts are none, the availability impact is high. The vulnerability requires user interaction for exploitation and has a local attack vector.

Technical Details of CVE-2023-4255

Let's explore the vulnerability description, affected systems and versions, as well as the exploitation mechanism associated with CVE-2023-4255.

Vulnerability Description

The vulnerability arises from an out-of-bounds write issue in the checkType() function within the W3M application. By supplying a specially crafted HTML file, attackers can trigger this flaw, leading to potential application crashes and denial of service.

Affected Systems and Versions

The vulnerability affects the following products:

W3M
Fedora
Extra Packages for Enterprise Linux

Exploitation Mechanism

Exploitation of CVE-2023-4255 involves providing a malicious HTML file to the W3M binary, exploiting the out-of-bounds write issue in the checkType() function.

Mitigation and Prevention

In this section, we will discuss immediate steps to take, long-term security practices, and the importance of patching and updates.

Immediate Steps to Take

Users and administrators should apply patches or updates provided by the vendor promptly to mitigate the risk posed by CVE-2023-4255. Additionally, restricting access to potentially malicious files can also help prevent exploitation.

Long-Term Security Practices

Implementing secure coding practices, regularly updating software, and conducting security assessments can enhance overall resilience against such vulnerabilities in the long term.

Patching and Updates

Regularly monitor official sources for security advisories and updates related to W3M and associated packages. Applying patches as soon as they are released is crucial in maintaining a secure environment.