CVE-2019-20934 : Exploit Details and Defense Strategies

A problem was found in the Linux kernel version prior to 5.2.6. This vulnerability, identified as CID-16d51a590a8c, affects NUMA systems and involves a use-after-free issue in the Linux fair scheduler's show_numa_stats() function.

Understanding CVE-2019-20934

This CVE pertains to a specific vulnerability in the Linux kernel that impacts NUMA systems.

What is CVE-2019-20934?

The vulnerability in the Linux kernel version before 5.2.6 involves a use-after-free issue in the show_numa_stats() function of the fair scheduler when running on NUMA systems. This problem arises due to inappropriate freeing of NUMA fault statistics, also known as CID-16d51a590a8c.

The Impact of CVE-2019-20934

The vulnerability can be exploited by attackers to potentially execute arbitrary code or cause a denial of service (DoS) on affected systems.

Technical Details of CVE-2019-20934

This section provides more in-depth technical information about the CVE.

Vulnerability Description

The issue in the Linux kernel before version 5.2.6 leads to a use-after-free vulnerability in the fair scheduler's show_numa_stats() function on NUMA systems.

Affected Systems and Versions

Affected Version: Linux kernel versions prior to 5.2.6
Systems: NUMA systems

Exploitation Mechanism

The vulnerability can be exploited by malicious actors to trigger the use-after-free issue in the show_numa_stats() function, potentially leading to unauthorized code execution or DoS attacks.

Mitigation and Prevention

Protecting systems from CVE-2019-20934 requires immediate actions and long-term security measures.

Immediate Steps to Take

Update to Linux kernel version 5.2.6 or later to mitigate the vulnerability.
Monitor for any unusual system behavior that could indicate exploitation.

Long-Term Security Practices

Regularly update and patch the Linux kernel to address known vulnerabilities.
Implement proper access controls and network segmentation to limit the impact of potential attacks.

Patching and Updates

Apply security patches promptly to ensure that systems are protected against known vulnerabilities.