CVE-2021-3330 : What You Need to Know

This article provides an overview of CVE-2021-3330, a vulnerability in Zephyr that can lead to Remote Code Execution (RCE) and Denial of Service (DoS) attacks.

Understanding CVE-2021-3330

CVE-2021-3330 is a critical vulnerability in Zephyr that results from linked-list corruption in the forged fragment list sorting process, leading to a large out-of-bounds write scenario. Zephyr versions equal to or greater than 2.4.0 are affected, containing an Out-of-bounds Write flaw (CWE-787).

What is CVE-2021-3330?

The CVE-2021-3330 vulnerability in Zephyr is categorized as a Remote Code Execution (RCE) and Denial of Service (DoS) issue due to linked-list corruption during the sorting process of forged fragment lists.

The Impact of CVE-2021-3330

The impact of CVE-2021-3330 is significant, with a high base severity score of 7.1 according to the CVSS v3.1 metrics. The vulnerability can result in RCE and DoS attacks on systems running affected versions of Zephyr.

Technical Details of CVE-2021-3330

CVE-2021-3330 is characterized by linked-list corruption leading to out-of-bounds write scenarios, posing a serious risk to the integrity and availability of systems.

Vulnerability Description

The vulnerability allows for large out-of-bounds writes during forged fragment list sorting, enabling attackers to potentially execute arbitrary code or disrupt system operations.

Affected Systems and Versions

Zephyr versions equal to or greater than 2.4.0 are vulnerable to CVE-2021-3330, impacting systems utilizing these versions of the Zephyr operating system.

Exploitation Mechanism

Exploiting this vulnerability involves manipulating the forged fragment list sorting process in a way that triggers the out-of-bounds write, potentially leading to RCE or DoS conditions.

Mitigation and Prevention

To safeguard systems from CVE-2021-3330, immediate actions and long-term security practices are essential.

Immediate Steps to Take

It is crucial to apply patches or updates provided by Zephyr to address the vulnerability. Organizations should also monitor for any signs of exploitation or unusual system behavior.

Long-Term Security Practices

Implementing robust security measures, conducting regular security assessments, and staying informed about software vulnerabilities are key for long-term protection against similar threats.

Patching and Updates

Keeping Zephyr software up to date with the latest security patches and releases is critical in mitigating the risks associated with CVE-2021-3330.