CVE-2019-20636 Explained : Impact and Mitigation

An issue was discovered in the Linux kernel prior to version 5.4.12. The vulnerability allows for out-of-bounds writes through the manipulation of a specially crafted keycode table.

Understanding CVE-2019-20636

In the Linux kernel before version 5.4.12, a vulnerability exists in the file drivers/input/input.c, enabling out-of-bounds writes via a crafted keycode table.

What is CVE-2019-20636?

The vulnerability in the Linux kernel allows for out-of-bounds writes by manipulating a specially crafted keycode table, particularly in the input_set_keycode function.

The Impact of CVE-2019-20636

The vulnerability could be exploited by attackers to perform out-of-bounds writes, potentially leading to arbitrary code execution or a system crash.

Technical Details of CVE-2019-20636

The technical details of the CVE-2019-20636 vulnerability are as follows:

Vulnerability Description

The issue in drivers/input/input.c allows for out-of-bounds writes through a specially crafted keycode table manipulation.

Affected Systems and Versions

Affected systems: Linux kernel versions before 5.4.12
Affected components: drivers/input/input.c

Exploitation Mechanism

The vulnerability can be exploited by manipulating a specially crafted keycode table, particularly in the input_set_keycode function.

Mitigation and Prevention

To mitigate the CVE-2019-20636 vulnerability, follow these steps:

Immediate Steps to Take

Apply the official patch provided by the Linux kernel maintainers
Monitor vendor security advisories for updates

Long-Term Security Practices

Regularly update the Linux kernel to the latest version
Implement proper input validation mechanisms to prevent similar vulnerabilities

Patching and Updates

Ensure timely installation of security patches released by the Linux kernel maintainers