CVE-2023-4147 : Vulnerability Insights and Analysis

A local user can exploit a use-after-free flaw in the Linux kernel's Netfilter functionality with NFTA_RULE_CHAIN_ID to crash the system or gain escalated privileges.

Understanding CVE-2023-4147

This CVE pertains to a vulnerability in the Linux kernel that can be exploited by a local user to cause a denial of service or potentially elevate their privileges on the system.

What is CVE-2023-4147?

CVE-2023-4147 involves a use-after-free flaw in the Linux kernel's Netfilter functionality that occurs when adding a rule with NFTA_RULE_CHAIN_ID. This vulnerability can be leveraged by a local user to crash the system or potentially escalate their privileges.

The Impact of CVE-2023-4147

The impact of CVE-2023-4147 is rated as high in terms of confidentiality, integrity, and availability. With a CVSS base score of 7.8, this vulnerability poses a significant risk to affected systems if exploited.

Technical Details of CVE-2023-4147

This section provides more in-depth technical details regarding the vulnerability.

Vulnerability Description

The vulnerability lies in the Linux kernel's Netfilter functionality, where a use-after-free flaw can be triggered by adding a rule with NFTA_RULE_CHAIN_ID. This flaw enables a local user to crash the system or potentially escalate their privileges.

Affected Systems and Versions

Affected Products:
Red Hat Enterprise Linux 9

Red Hat Enterprise Linux 9.0 Extended Update Support

Fedora
Affected Version:
kernel

Exploitation Mechanism

The vulnerability can be exploited by a local user through crafted input related to the Netfilter functionality, specifically when adding a rule with NFTA_RULE_CHAIN_ID, leading to the use-after-free condition.

Mitigation and Prevention

To address CVE-2023-4147, the following steps can be taken to mitigate the risks associated with this vulnerability.

Immediate Steps to Take

Update to the latest patched versions provided by the vendor.
Monitor vendor advisories and apply recommended security updates promptly.

Long-Term Security Practices

Implement the principle of least privilege to restrict user access.
Regularly update and patch systems to mitigate known vulnerabilities.
Conduct security assessments and audits to identify and address potential security gaps.

Patching and Updates

Ensure that the affected systems are updated with the latest patches and security updates released by the vendor to mitigate the risks associated with CVE-2023-4147.