CVE-2018-6925 : What You Need to Know

A vulnerability in FreeBSD versions before 11.2-STABLE(r338986), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338985), and 10.4-RELEASE-p13 could allow an unprivileged authenticated local user to trigger a kernel crash through a NULL pointer dereference.

Understanding CVE-2018-6925

This CVE entry details a denial of service vulnerability in FreeBSD.

What is CVE-2018-6925?

CVE-2018-6925 is a vulnerability in FreeBSD versions prior to specific releases that mishandle IPv6 protocol control block flags, potentially leading to a kernel crash when certain paths fail. The issue can be exploited by an unprivileged authenticated local user.

The Impact of CVE-2018-6925

The vulnerability can result in a denial of service condition, causing the kernel to crash and disrupt system operations.

Technical Details of CVE-2018-6925

This section provides technical insights into the vulnerability.

Vulnerability Description

The vulnerability arises from the improper handling of IPv6 protocol control block flags in FreeBSD versions before specific releases, leading to a NULL pointer dereference and subsequent kernel crash.

Affected Systems and Versions

FreeBSD 11.2 before 11.2-RELEASE-p4
FreeBSD 11.1 before 11.1-RELEASE-p15
FreeBSD 10.x before 10.4-RELEASE-p13

Exploitation Mechanism

The vulnerability can be exploited by an unprivileged authenticated local user, triggering a NULL pointer dereference and crashing the kernel.

Mitigation and Prevention

Protecting systems from CVE-2018-6925 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply the necessary patches provided by FreeBSD to address the vulnerability.
Monitor security advisories for updates and follow best practices for system hardening.

Long-Term Security Practices

Regularly update FreeBSD systems to the latest stable releases to mitigate known vulnerabilities.
Implement the principle of least privilege to restrict user access and minimize the impact of potential exploits.

Patching and Updates

Ensure timely installation of security patches and updates released by FreeBSD to remediate the vulnerability.