CVE-2019-15921 Explained : Impact and Mitigation

A problem has been identified in the Linux kernel version prior to 5.0.6. The issue arises from a memory leak when idr_alloc() encounters a failure within genl_register_family() located in net/netlink/genetlink.c.

Understanding CVE-2019-15921

An issue was discovered in the Linux kernel before 5.0.6. There is a memory leak issue when idr_alloc() fails in genl_register_family() in net/netlink/genetlink.c.

What is CVE-2019-15921?

CVE-2019-15921 is a vulnerability in the Linux kernel before version 5.0.6 that leads to a memory leak when idr_alloc() fails within genl_register_family() in net/netlink/genetlink.c.

The Impact of CVE-2019-15921

This vulnerability could be exploited by an attacker to cause a denial of service (DoS) condition on the affected system.

Technical Details of CVE-2019-15921

The following are the technical details of CVE-2019-15921:

Vulnerability Description

The vulnerability stems from a memory leak in the Linux kernel before version 5.0.6, specifically when idr_alloc() fails within genl_register_family() in net/netlink/genetlink.c.

Affected Systems and Versions

Linux kernel versions prior to 5.0.6 are affected by this vulnerability.

Exploitation Mechanism

An attacker could exploit this vulnerability by triggering the memory leak when idr_alloc() fails within genl_register_family() in net/netlink/genetlink.c.

Mitigation and Prevention

Here are the steps to mitigate and prevent the CVE-2019-15921 vulnerability:

Immediate Steps to Take

Update the Linux kernel to version 5.0.6 or later to address the memory leak issue.
Monitor system logs for any signs of abnormal memory consumption.

Long-Term Security Practices

Regularly update the Linux kernel and apply security patches promptly.
Implement proper access controls and network segmentation to reduce the attack surface.

Patching and Updates

Stay informed about security advisories and patches released by Linux kernel maintainers.
Follow best practices for secure coding and configuration to prevent memory leaks and other vulnerabilities.