CVE-2023-7192 : Vulnerability Insights and Analysis

This CVE-2023-7192 article provides detailed information about a vulnerability in the Linux Kernel that could potentially lead to a denial of service attack.

Understanding CVE-2023-7192

CVE-2023-7192 is a moderate-severity vulnerability found in the Linux Kernel. It specifically involves a refcount leak in ctnetlink_create_conntrack, which is located in net/netfilter/nf_conntrack_netlink.c.

What is CVE-2023-7192?

A memory leak issue in ctnetlink_create_conntrack in the Linux Kernel could be exploited by a local attacker with CAP_NET_ADMIN privileges. This vulnerability could result in a denial of service (DoS) attack due to a refcount overflow.

The Impact of CVE-2023-7192

The impact of CVE-2023-7192 is considered moderate, as it could potentially allow a local attacker to disrupt the affected system's availability.

Technical Details of CVE-2023-7192

This section delves into the technical aspects of CVE-2023-7192, including the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability arises from a memory leak problem in the ctnetlink_create_conntrack function in the Linux Kernel, specifically in the nf_conntrack_netlink.c file.

Affected Systems and Versions

Unaffected Versions: Kernel 6.3-rc1
Affected Versions:
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9
Fedora

Exploitation Mechanism

The vulnerability can be exploited by a local attacker with CAP_NET_ADMIN privileges to trigger a denial of service (DoS) attack by causing a refcount overflow.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-7192, prompt action is essential. Here are some steps to prevent potential exploitation and secure affected systems.

Immediate Steps to Take

Disable user namespaces in non-containerized deployments of Red Hat Enterprise Linux 8 by setting user.max_user_namespaces to 0.
Avoid loading the affected netfilter module until a fix is available by utilizing a blacklist mechanism.

Long-Term Security Practices

Implement secure coding practices, regular security updates, and security monitoring to reduce the likelihood of successful attacks leveraging this vulnerability.

Patching and Updates

Stay informed about security updates and patches released by the Linux Kernel and Red Hat for the affected versions to address CVE-2023-7192 effectively.