CVE-2018-1000200 : What You Need to Know

The Linux Kernel versions 4.14, 4.15, and 4.16 are affected by a vulnerability that can lead to the killing of large mlocked processes due to out of memory (OOM) conditions.

Understanding CVE-2018-1000200

This CVE involves a null pointer dereference issue in the Linux Kernel versions 4.14, 4.15, and 4.16, potentially resulting in OOM killing of large mlocked processes.

What is CVE-2018-1000200?

The vulnerability occurs when the final thread of an oom killed process invokes exit_mmap(), leading to munlock_vma_pages_all() for mlocked vmas. This issue can coincide with the unmap_page_range() function of the oom reaper, causing the VM_LOCKED bit of the vma to be cleared before munlocking.

The Impact of CVE-2018-1000200

The vulnerability can result in the killing of large mlocked processes due to OOM conditions, affecting the stability and performance of systems running the Linux Kernel versions 4.14, 4.15, and 4.16.

Technical Details of CVE-2018-1000200

The technical aspects of the CVE.

Vulnerability Description

Null pointer dereference in Linux Kernel versions 4.14, 4.15, and 4.16
OOM killing of large mlocked processes

Affected Systems and Versions

Linux Kernel versions 4.14, 4.15, and 4.16

Exploitation Mechanism

Final thread of an oom killed process invoking exit_mmap()
munlock_vma_pages_all() for mlocked vmas
Unmap_page_range() function of the oom reaper

Mitigation and Prevention

Steps to address the CVE.

Immediate Steps to Take

Apply patches provided by the Linux Kernel maintainers
Monitor system performance for any unusual behavior

Long-Term Security Practices

Regularly update the Linux Kernel to the latest stable version
Implement memory management best practices to prevent OOM conditions

Patching and Updates

Refer to official vendor advisories for patching instructions and updates