CVE-2021-38204 : Exploit Details and Defense Strategies

A denial of service vulnerability in the Linux kernel before version 5.13.6, tracked as CVE-2021-38204, allows physically proximate attackers to trigger a use-after-free and panic via specific actions.

Understanding CVE-2021-38204

This section delves into the details of the CVE-2021-38204 vulnerability in the Linux kernel.

What is CVE-2021-38204?

The CVE-2021-38204 vulnerability exists in drivers/usb/host/max3421-hcd.c in the Linux kernel. It enables nearby attackers to initiate a denial of service attack by unmounting a MAX-3421 USB device in particular scenarios.

The Impact of CVE-2021-38204

The impact of this vulnerability is the exploitation of a use-after-free issue leading to a system panic, potentially resulting in a denial of service condition.

Technical Details of CVE-2021-38204

Explore the technical specifics surrounding CVE-2021-38204 to better understand the nature of this security flaw.

Vulnerability Description

The flaw in drivers/usb/host/max3421-hcd.c within the Linux kernel allows attackers in close proximity to disrupt system operations through a use-after-free condition, culminating in a system panic.

Affected Systems and Versions

All Linux kernel versions prior to 5.13.6 are vulnerable to CVE-2021-38204, exposing systems to the risk of denial of service attacks when certain conditions are met.

Exploitation Mechanism

Physically proximate threat actors can exploit this vulnerability by detaching a MAX-3421 USB device under specific circumstances, triggering the use-after-free issue and subsequent system panic.

Mitigation and Prevention

Learn how to mitigate and prevent the CVE-2021-38204 vulnerability to enhance your system's security posture.

Immediate Steps to Take

To address CVE-2021-38204, update the Linux kernel to version 5.13.6 or newer. Ensure that the MAX-3421 USB devices are disconnected safely to prevent exploitation of this vulnerability.

Long-Term Security Practices

Implement best security practices such as regular system updates, threat monitoring, and user awareness training to bolster your defense against potential attacks.

Patching and Updates

Stay informed about security patches and updates released by the Linux kernel maintainers to promptly address vulnerabilities like CVE-2021-38204 and safeguard your systems.