CVE-2023-6622 : Vulnerability Insights and Analysis

This CVE-2023-6622 affects the Linux kernel and specifically involves a null pointer dereference vulnerability in the

nft_dynset_init()

function in

net/netfilter/nft_dynset.c

in

nf_tables

. The vulnerability could be exploited by a local attacker with CAP_NET_ADMIN user privilege to trigger a denial of service.

Understanding CVE-2023-6622

This section delves into the specifics of CVE-2023-6622 vulnerability, its impact, technical details, affected systems, and mitigation strategies.

What is CVE-2023-6622?

The CVE-2023-6622 vulnerability is characterized by a null pointer dereference flaw in the Linux kernel's

nft_dynset_init()

function within the

nf_tables

module. This flaw could potentially enable a local attacker with specific privileges to cause a denial of service.

The Impact of CVE-2023-6622

The impact of this vulnerability is rated as moderate, with a CVSS base score of 5.5 out of 10. The attack complexity is classified as low, requires local access, and has a high availability impact. However, it does not affect confidentiality or integrity, only causing a denial of service.

Technical Details of CVE-2023-6622

This section provides insights into the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The null pointer dereference vulnerability in

nft_dynset_init()

function in

nf_tables

could be exploited by a local attacker with CAP_NET_ADMIN privileges to trigger a denial of service attack.

Affected Systems and Versions

The vulnerability affects various versions of Red Hat Enterprise Linux (6, 7, 8, 9) and the Fedora distribution where the

netfilter

module is utilized.

Exploitation Mechanism

Exploiting this vulnerability requires a local attacker with CAP_NET_ADMIN user privilege to manipulate the

nft_dynset_init()

function in

nf_tables

to trigger the null pointer dereference flaw.

Mitigation and Prevention

In response to CVE-2023-6622, several steps can be taken to mitigate the risk and prevent exploitation.

Immediate Steps to Take

One immediate mitigation measure is to prevent the affected

netfilter

module from loading onto the system until a fix is available. This can be achieved through a blacklist mechanism to avoid loading the driver at boot time.

Long-Term Security Practices

In the long term, ensuring timely patching and updating of affected systems is crucial to address vulnerabilities like CVE-2023-6622. Regular security assessments and monitoring can also enhance overall system security.

Patching and Updates

Keeping systems up to date with security patches and updates provided by vendors like Red Hat is essential to address known vulnerabilities and enhance system security against potential threats. Regularly checking for and applying patches can help prevent exploitation of CVE-2023-6622.