CVE-2023-39193 : Security Advisory and Response

A detailed overview of the CVE-2023-39193 vulnerability affecting the Linux kernel's netfilter subsystem.

Understanding CVE-2023-39193

This section provides an insight into the nature of the vulnerability.

What is CVE-2023-39193?

CVE-2023-39193 is a moderate-severity vulnerability found in the Netfilter subsystem in the Linux kernel. It arises due to inadequate validation of the flag_count field, enabling a local privileged attacker to trigger an out-of-bounds read, potentially leading to a crash or exposure of sensitive information.

The Impact of CVE-2023-39193

The impact includes local attackers with CAP_NET_ADMIN privileges exploiting the flaw to read out-of-bounds, which may result in system crashes or disclosure of confidential data.

Technical Details of CVE-2023-39193

Delve into the specifics of the vulnerability.

Vulnerability Description

The issue originates from the sctp_mt_check function not properly validating the flag_count field, allowing local attackers to execute out-of-bounds reads.

Affected Systems and Versions

The vulnerability affects various versions of Red Hat Enterprise Linux, including 6, 7, 8, and 9, along with Fedora.

Exploitation Mechanism

Attackers with CAP_NET_ADMIN privileges locally can exploit the flaw to trigger an out-of-bounds read, leading to crashes or exposure of sensitive information.

Mitigation and Prevention

Learn how to address and prevent the CVE-2023-39193 vulnerability.

Immediate Steps to Take

To mitigate the issue, prevent the affected

xt_sctp

kernel module from loading. Refer to Red Hat's solution for instructions on how to blacklist a kernel module.

Long-Term Security Practices

Implement robust security measures, such as regular security updates and patches, to safeguard systems against potential exploits.

Patching and Updates

Stay informed about security patches and updates for the Linux kernel to address known vulnerabilities and enhance system security.