CVE-2021-3321 Explained : Impact and Mitigation
Learn about CVE-2021-3321, an Integer Underflow vulnerability in Zephyr versions >=2.4.0 with a CVSS base score of 7.5. Understand the impact, affected systems, and mitigation strategies.
Integer Underflow in Zephyr in IEEE 802154 Fragment Reassembly Header Removal is a critical vulnerability identified in Zephyr versions >=2.4.0. This CVE, with a CVSS base score of 7.5, poses a high risk due to Integer Overflow to Buffer Overflow (CWE-680).
Understanding CVE-2021-3321
This section provides insights into the nature of the CVE and its potential impact.
What is CVE-2021-3321?
The CVE-2021-3321 involves an Integer Underflow in Zephyr in IEEE 802154 Fragment Reassembly Header Removal. Zephyr versions >=2.4.0 are affected by this vulnerability, leading to Integer Overflow and subsequent Buffer Overflow (CWE-680).
The Impact of CVE-2021-3321
The vulnerability has a base score of 7.5 (High) according to CVSS v3.1 metrics. It has a high availability impact while keeping the confidentiality and integrity impact low. The attack complexity is considered high with no privileges required.
Technical Details of CVE-2021-3321
In this section, we delve into the technical aspects of the CVE.
Vulnerability Description
The vulnerability arises due to an Integer Underflow in Zephyr in IEEE 802154 Fragment Reassembly Header Removal, leading to Integer Overflow and presenting a Buffer Overflow risk.
Affected Systems and Versions
Zephyr versions >=2.4.0 are confirmed to be impacted by this vulnerability.
Exploitation Mechanism
The vulnerability can be exploited through an adjacent network attack vector.
Mitigation and Prevention
This section outlines the steps to mitigate and prevent the exploitation of CVE-2021-3321.
Immediate Steps to Take
Immediate actions include applying relevant patches, updates, or workarounds provided by Zephyr to address the vulnerability.
Long-Term Security Practices
In the long term, organizations are advised to keep software versions up to date, conduct regular security assessments, and implement robust security protocols.
Patching and Updates
Regularly check for security advisories from Zephyr and promptly apply patches and updates to ensure system security.