CVE-2019-12881 Explained : Impact and Mitigation

This CVE involves a vulnerability in the Linux kernel version 4.15.0 on Ubuntu 18.04.2 that can be exploited by local users to trigger a denial of service situation or potentially cause other unknown impacts.

Understanding CVE-2019-12881

This section provides insights into the nature and impact of the CVE.

What is CVE-2019-12881?

The function i915_gem_userptr_get_pages in the Linux kernel version 4.15.0 on Ubuntu 18.04.2 can be exploited by local users to trigger a denial of service situation or potentially cause other unknown impacts by making malicious ioctl calls to /dev/dri/card0.

The Impact of CVE-2019-12881

The vulnerability can lead to a NULL pointer dereference and BUG, resulting in a denial of service situation or other unspecified impacts.

Technical Details of CVE-2019-12881

This section delves into the technical aspects of the CVE.

Vulnerability Description

The vulnerability exists in the i915_gem_userptr_get_pages function in drivers/gpu/drm/i915/i915_gem_userptr.c in the Linux kernel 4.15.0 on Ubuntu 18.04.2.

Affected Systems and Versions

Linux kernel version 4.15.0 on Ubuntu 18.04.2

Exploitation Mechanism

Local users can exploit the vulnerability by making malicious ioctl calls to /dev/dri/card0.

Mitigation and Prevention

Here are the steps to mitigate and prevent exploitation of CVE-2019-12881.

Immediate Steps to Take

Apply security patches provided by the Linux kernel maintainers.
Monitor and restrict access to /dev/dri/card0.

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version.
Implement the principle of least privilege to limit user access.

Patching and Updates

Stay informed about security advisories from Ubuntu and the Linux kernel community.
Promptly apply patches and updates to address known vulnerabilities.