CVE-2023-42755 : What You Need to Know

A flaw has been identified in the IPv4 Resource Reservation Protocol (RSVP) classifier within the Linux kernel. The vulnerability, assigned the CVE-2023-42755, can lead to an out-of-bounds read in the

rsvp_classify

function, potentially allowing a local user to crash the system and cause a denial of service.

Understanding CVE-2023-42755

This section delves into the details of the CVE-2023-42755 vulnerability.

What is CVE-2023-42755?

CVE-2023-42755 is a vulnerability found in the IPv4 Resource Reservation Protocol (RSVP) classifier in the Linux kernel. It arises due to the xprt pointer going beyond the linear part of the skb, resulting in an out-of-bounds read in the

rsvp_classify

function.

The Impact of CVE-2023-42755

The vulnerability may enable a local user to crash the system, potentially leading to a denial of service scenario.

Technical Details of CVE-2023-42755

This section outlines the technical aspects of the CVE-2023-42755 vulnerability.

Vulnerability Description

The issue involves an out-of-bounds read in the

rsvp_classify

function within the IPv4 Resource Reservation Protocol (RSVP) classifier in the Linux kernel.

Affected Systems and Versions

Systems running Red Hat Enterprise Linux versions 6, 7, 8, and 9 are affected. The affected packages include 'kernel' and 'kernel-rt' for various versions.

Exploitation Mechanism

The vulnerability allows a local user to trigger an out-of-bounds read by manipulating the xprt pointer within the skb structure.

Mitigation and Prevention

In this section, we discuss the measures to mitigate and prevent the CVE-2023-42755 vulnerability.

Immediate Steps to Take

Users are advised to prevent the affected

cls_rsvp

kernel module from loading as a workaround. Refer to the provided link for instructions on how to blacklist a kernel module.

Long-Term Security Practices

Implementing regular security updates and patches is crucial in maintaining system integrity and safeguarding against potential vulnerabilities.

Patching and Updates

Regularly monitor security advisories from relevant vendors and promptly apply patches to address known vulnerabilities.