CVE-2021-3659 : Exploit Details and Defense Strategies

A NULL pointer dereference flaw was found in the Linux kernel's IEEE 802.15.4 wireless networking subsystem, allowing a local user to crash the system, affecting system availability.

Understanding CVE-2021-3659

This CVE identifies a critical vulnerability in the Linux kernel related to the IEEE 802.15.4 wireless networking subsystem, leading to a NULL pointer dereference flaw when closing the LR-WPAN connection.

What is CVE-2021-3659?

A NULL pointer dereference flaw occurs in the Linux kernel's IEEE 802.15.4 wireless networking subsystem, impacting the way users close LR-WPAN connections, enabling a local user to crash the system.

The Impact of CVE-2021-3659

The highest risk resulting from this vulnerability is the potential compromise of system availability, as an attacker with local access could exploit the flaw to disrupt system operations.

Technical Details of CVE-2021-3659

This section delves into the technical specifics of the CVE.

Vulnerability Description

The vulnerability stems from a NULL pointer dereference within the Linux kernel's IEEE 802.15.4 wireless networking subsystem, triggered by a user action when closing LR-WPAN connections.

Affected Systems and Versions

The vulnerability affects the Linux Kernel and specifically versions before Kernel 5.12, making systems running on earlier versions susceptible to exploitation.

Exploitation Mechanism

Local adversaries can exploit this CVE by leveraging the flaw in the IEEE 802.15.4 wireless networking subsystem, causing a system crash upon the user's attempt to close LR-WPAN connections.

Mitigation and Prevention

Protecting systems from CVE-2021-3659 requires immediate action and long-term security measures.

Immediate Steps to Take

Users are advised to update their Linux Kernel to version 5.12 or above to mitigate the vulnerability. Additionally, monitor system logs for any suspicious activities that could indicate an exploit attempt.

Long-Term Security Practices

Implement regular security patches and updates, conduct routine security audits, and restrict user permissions to minimize the risk of unauthorized system access.

Patching and Updates

Stay informed about security bulletins and advisories from official sources like Red Hat to promptly apply patches addressing CVE-2021-3659 vulnerabilities.