CVE-2018-6921 Explained : Impact and Mitigation
Learn about CVE-2018-6921 affecting FreeBSD versions prior to 11.1-RELEASE-p10. Authenticated local users could access privileged kernel data, posing a security risk.
CVE-2018-6921 was published on May 8, 2018, affecting FreeBSD versions prior to 11.1-RELEASE-p10. The vulnerability allowed authenticated local users to access small portions of privileged kernel data.
Understanding CVE-2018-6921
Prior to version 11.1-STABLE(r332066) and 11.1-RELEASE-p10 of FreeBSD, an issue in the network subsystem led to the exposure of kernel memory to userland processes.
What is CVE-2018-6921?
- Insufficient memory initialization in FreeBSD versions allowed disclosure of kernel memory to userland processes.
- Authenticated local users with limited privileges could access privileged kernel data.
The Impact of CVE-2018-6921
The vulnerability could be exploited by authenticated local users to gain unauthorized access to kernel memory, potentially leading to further system compromise.
Technical Details of CVE-2018-6921
The technical aspects of the vulnerability are as follows:
Vulnerability Description
- Insufficient memory initialization in the network subsystem of FreeBSD versions.
- Exposure of limited kernel memory to userland processes.
Affected Systems and Versions
- Product: FreeBSD
- Vendor: FreeBSD
- Affected Versions: FreeBSD 11.x prior to 11.1-RELEASE-p10
Exploitation Mechanism
- Authenticated local users with limited privileges could exploit the vulnerability to access small portions of privileged kernel data.
Mitigation and Prevention
To address CVE-2018-6921, consider the following steps:
Immediate Steps to Take
- Apply the necessary patches provided by FreeBSD to mitigate the vulnerability.
- Monitor system logs for any suspicious activities that may indicate exploitation.
Long-Term Security Practices
- Regularly update FreeBSD systems to the latest stable releases to ensure security patches are applied.
- Implement the principle of least privilege to restrict user access and minimize the impact of potential vulnerabilities.
Patching and Updates
- Stay informed about security advisories from FreeBSD and promptly apply relevant patches to secure the system.