CVE-2019-5601 Explained : Impact and Mitigation

A vulnerability in the FFS implementation of FreeBSD versions 12.0-STABLE, 12.0-RELEASE, 11.2-STABLE, and 11.2-RELEASE allows for kernel information leakage.

Understanding CVE-2019-5601

This CVE involves a bug in the FFS implementation of specific FreeBSD versions, leading to potential kernel information leakage.

What is CVE-2019-5601?

In FreeBSD versions 12.0-STABLE, 12.0-RELEASE, 11.2-STABLE, and 11.2-RELEASE, a flaw in the FFS implementation results in uninitialized directory entry padding being written from kernel stack memory to the disk.

The Impact of CVE-2019-5601

This vulnerability could allow an attacker to access sensitive kernel information, potentially leading to further exploitation or unauthorized access to the system.

Technical Details of CVE-2019-5601

Vulnerability Description

The bug in the FFS implementation causes up to three bytes of kernel stack memory to be written as uninitialized directory entry padding on the disk.

Affected Systems and Versions

FreeBSD 12.0 before 12.0-RELEASE-p7
FreeBSD 11.2 before 11.2-RELEASE-p11

Exploitation Mechanism

The vulnerability allows for the leakage of kernel information due to the incorrect handling of directory entry padding.

Mitigation and Prevention

Immediate Steps to Take

Apply the necessary patches provided by FreeBSD to address this vulnerability.
Monitor security advisories for any updates or additional mitigation steps.

Long-Term Security Practices

Regularly update FreeBSD systems to the latest stable releases to ensure all security patches are applied.
Implement proper access controls and monitoring mechanisms to detect any unauthorized access attempts.

Patching and Updates

Ensure timely installation of security patches and updates released by FreeBSD to mitigate the risk of exploitation.