CVE-2021-20219 : Exploit Details and Defense Strategies

A denial of service vulnerability was found in n_tty_receive_char_special in drivers/tty/n_tty.c of the Linux kernel, allowing a local attacker with normal user privilege to delay the loop and threaten system availability.

Understanding CVE-2021-20219

This section provides insight into the nature of the CVE-2021-20219 vulnerability.

What is CVE-2021-20219?

CVE-2021-20219 is a denial of service vulnerability discovered in the Linux kernel's n_tty_receive_char_special function.

The Impact of CVE-2021-20219

The vulnerability allows a local attacker to disrupt system availability by delaying the loop due to a missing sanity check.

Technical Details of CVE-2021-20219

In this section, we delve into the technical aspects of CVE-2021-20219.

Vulnerability Description

The flaw arises from n_tty_receive_char_special in drivers/tty/n_tty.c, making the system susceptible to denial of service attacks.

Affected Systems and Versions

The vulnerability affects systems running the Linux kernel version 4.18.

Exploitation Mechanism

An attacker with normal user privileges can exploit the flaw to disrupt system availability.

Mitigation and Prevention

Here, we explore measures to mitigate and prevent exploitation of CVE-2021-20219.

Immediate Steps to Take

Users are advised to apply security patches promptly and monitor for any signs of exploitation.

Long-Term Security Practices

Implementing least privilege access and regular security audits can enhance overall system security.

Patching and Updates

Regularly updating the Linux kernel to the latest version is crucial in preventing exploitation of known vulnerabilities.