CVE-2021-43976 Explained : Impact and Mitigation

In the Linux kernel through 5.15.2, mwifiex_usb_recv in drivers/net/wireless/marvell/mwifiex/usb.c allows an attacker to cause a denial of service.

Understanding CVE-2021-43976

What is CVE-2021-43976?

CVE-2021-43976 is a vulnerability in the Linux kernel that enables an attacker to trigger a denial of service by connecting a crafted USB device.

The Impact of CVE-2021-43976

This vulnerability can be exploited by a malicious actor to cause a denial of service (skb_over_panic) on systems running the affected Linux kernel versions.

Technical Details of CVE-2021-43976

Vulnerability Description

The mwifiex_usb_recv function in drivers/net/wireless/marvell/mwifiex/usb.c within the Linux kernel allows an attacker to trigger a denial of service by exploiting a crafted USB device.

Affected Systems and Versions

Linux kernel through version 5.15.2

Exploitation Mechanism

An attacker with the ability to connect a specially crafted USB device can exploit this vulnerability, leading to a denial of service condition.

Mitigation and Prevention

Immediate Steps to Take

Apply the relevant security patches provided by Linux distributions promptly
Monitor sources for updates on this vulnerability

Long-Term Security Practices

Implement strict USB device control policies to prevent unauthorized or untrustworthy devices from being connected
Regularly update and patch the Linux kernel and associated drivers
Conduct security audits and assessments periodically to identify and mitigate potential vulnerabilities

Patching and Updates

Keep the Linux kernel and associated components up to date with the latest security patches from the official sources