CVE-2023-42756 Explained : Impact and Mitigation

A detailed analysis of CVE-2023-42756, a vulnerability found in the Netfilter subsystem of the Linux kernel, affecting various Red Hat Enterprise Linux versions.

Understanding CVE-2023-42756

This section delves into the nature of the vulnerability and its impact on affected systems.

What is CVE-2023-42756?

CVE-2023-42756 is a race condition vulnerability in the Linux kernel's Netfilter subsystem. It occurs due to a race condition between IPSET_CMD_ADD and IPSET_CMD_SWAP, leading to a potential kernel panic when

__ip_set_put

is invoked on the wrong set, potentially crashing the system.

The Impact of CVE-2023-42756

The vulnerability could be exploited by a local user to trigger a kernel panic, resulting in a denial of service (DoS) condition. It affects various Red Hat Enterprise Linux versions and Fedora.

Technical Details of CVE-2023-42756

This section provides technical details regarding the vulnerability, affected systems, and the exploitation mechanism.

Vulnerability Description

The flaw stems from a race condition between IPSET_CMD_ADD and IPSET_CMD_SWAP in the Netfilter subsystem, potentially leading to a kernel panic and system crash when

__ip_set_put

is incorrectly invoked.

Affected Systems and Versions

Affected systems include various versions of Red Hat Enterprise Linux and Fedora. Specific details are provided for each affected product and version.

Exploitation Mechanism

The vulnerability could be exploited by a local user to trigger the race condition, leading to a kernel panic and potential system crash.

Mitigation and Prevention

This section outlines steps for mitigating the vulnerability and preventing potential exploits.

Immediate Steps to Take

As mitigation options do not meet Red Hat Product Security criteria, immediate steps include monitoring vendor communications and applying patches promptly upon availability.

Long-Term Security Practices

Implementing secure coding practices, regular security updates, and monitoring security announcements can bolster long-term security posture.

Patching and Updates

Regularly applying security patches from vendors like Red Hat and Fedora is crucial in addressing known vulnerabilities and ensuring system security.