CVE-2024-0193: Security Advisory and Response

This CVE record describes a vulnerability in the netfilter subsystem of the Linux kernel that could allow a local unprivileged user with CAP_NET_ADMIN capability to escalate their privileges on the system.

Understanding CVE-2024-0193

This section will delve into the details of CVE-2024-0193, highlighting its impact and technical aspects.

What is CVE-2024-0193?

CVE-2024-0193 is a use-after-free flaw discovered in the netfilter subsystem of the Linux kernel. Specifically, the issue arises when the catchall element is garbage-collected while the pipapo set is removed, leading to the deactivation of the element twice. This can result in a use-after-free vulnerability on an NFT_CHAIN object or NFT_OBJECT object, enabling a local unprivileged user to escalate their privileges by exploiting this flaw.

The Impact of CVE-2024-0193

The impact of this vulnerability is rated as high due to its potential to allow a local unprivileged user to gain escalated privileges on the system. With a CVSS base score of 7.8, the confidentiality, integrity, and availability of affected systems could be compromised.

Technical Details of CVE-2024-0193

In this section, we will explore the vulnerability description, affected systems and versions, as well as the exploitation mechanism.

Vulnerability Description

The root cause of CVE-2024-0193 lies in a use-after-free issue within the netfilter subsystem of the Linux kernel. This flaw can be leveraged by a local unprivileged user to elevate their privileges on the system.

Affected Systems and Versions

The following systems are affected by CVE-2024-0193:

Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9
Fedora

Exploitation Mechanism

To exploit this vulnerability, an attacker would need local access to the system and CAP_NET_ADMIN capability. By triggering the use-after-free flaw in the netfilter subsystem, the attacker can potentially escalate their privileges.

Mitigation and Prevention

This section focuses on the steps that can be taken to mitigate the risk associated with CVE-2024-0193.

Immediate Steps to Take

For non-containerized deployments of Red Hat Enterprise Linux 8, consider disabling user namespaces by setting user.max_user_namespaces to 0.
In containerized deployments like Red Hat OpenShift Container Platform, alternative mitigations may need to be evaluated.

Long-Term Security Practices

Implementing strong access control measures and regularly updating the system can help prevent such vulnerabilities from being exploited.

Patching and Updates

Stay informed about security updates and patches released by Red Hat to address CVE-2024-0193. Regularly apply patches to ensure the security of your systems.