CVE-2020-7462 : Vulnerability Insights and Analysis

A use-after-free vulnerability in FreeBSD 11.3-RELEASE before p13 allows for unintended kernel behavior, potentially leading to a kernel panic.

Understanding CVE-2020-7462

In FreeBSD versions 11.4-PRERELEASE before r360733 and 11.3-RELEASE before p13, a specific kernel handling issue can trigger a use-after-free bug, resulting in potential system instability.

What is CVE-2020-7462?

This CVE involves improper mbuf handling in the kernel, leading to a use-after-free bug when sending IPv6 Hop-by-Hop options over the loopback interface. The use-after-free scenario can cause unexpected kernel behavior, including kernel panics.

The Impact of CVE-2020-7462

The vulnerability can be exploited to induce a use-after-free condition, potentially resulting in a kernel panic and system instability.

Technical Details of CVE-2020-7462

The technical aspects of this CVE include:

Vulnerability Description

Improper mbuf handling in the kernel triggers a use-after-free bug when specific IPv6 packets are sent over the loopback interface.

Affected Systems and Versions

Product: FreeBSD
Versions Affected: FreeBSD 11.3-RELEASE before p13

Exploitation Mechanism

The vulnerability is exploited by sending IPv6 Hop-by-Hop options over the loopback interface, causing a use-after-free bug.

Mitigation and Prevention

To address CVE-2020-7462, consider the following steps:

Immediate Steps to Take

Apply the necessary patches provided by FreeBSD promptly.
Monitor official FreeBSD security advisories for updates and mitigation guidance.

Long-Term Security Practices

Regularly update FreeBSD systems to the latest stable releases.
Implement network segmentation and access controls to minimize the impact of potential exploits.

Patching and Updates

Ensure timely installation of security patches and updates from FreeBSD to mitigate the vulnerability effectively.