CVE-2023-4244 : Exploit Details and Defense Strategies

This CVE, assigned by Google, related to a use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component that can lead to privilege escalation.

Understanding CVE-2023-4244

This CVE, identified in the Linux kernel, presents a potential risk of local privilege escalation due to a use-after-free vulnerability in the netfilter: nf_tables component.

What is CVE-2023-4244?

The CVE-2023-4244 vulnerability in the Linux kernel's netfilter: nf_tables component is caused by a race condition between nf_tables netlink control plane transaction and nft_set element garbage collection. This race condition can lead to an underflow of the reference counter, resulting in a use-after-free vulnerability.

The Impact of CVE-2023-4244

The impact of CVE-2023-4244 is classified as a privilege escalation vulnerability (CAPEC-233), allowing attackers to potentially elevate their privileges on the affected system.

Technical Details of CVE-2023-4244

This section provides detailed technical information about the vulnerability, its affected systems, and the exploitation mechanism.

Vulnerability Description

The use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component arises due to a race condition, enabling attackers to misuse the reference counter and achieve privilege escalation.

Affected Systems and Versions

The affected system is the Linux kernel's netfilter: nf_tables component with versions less than 6.5. It is crucial to upgrade past commit 3e91b0ebd994635df2346353322ac51ce84ce6d8 to mitigate this vulnerability.

Exploitation Mechanism

Exploiting CVE-2023-4244 involves triggering the race condition between nf_tables netlink control plane transaction and nft_set element garbage collection to manipulate the reference counter.

Mitigation and Prevention

To safeguard systems from CVE-2023-4244 and prevent potential exploitation, immediate steps, security best practices, and patching measures need to be implemented.

Immediate Steps to Take

Considering the severity of the vulnerability, it is recommended to update the affected systems beyond commit 3e91b0ebd994635df2346353322ac51ce84ce6d8 to mitigate the risk of privilege escalation.

Long-Term Security Practices

In the long term, enforcing robust security practices, regular system updates, and monitoring for any suspicious activities can help prevent similar vulnerabilities from being exploited.

Patching and Updates

Regularly applying patches and updates released by the Linux kernel team is essential to ensure that the system is protected against known vulnerabilities like CVE-2023-4244.