CVE-2021-34261 Explained : Impact and Mitigation

This article provides an overview of CVE-2021-34261, detailing the vulnerability, its impact, technical details, and mitigation steps.

Understanding CVE-2021-34261

CVE-2021-34261 is a vulnerability in STMicroelectronics STM32Cube Middleware v1.8.0 and below that leads to denial of service by causing the system to hang when attempting to enable a remote wake-up feature.

What is CVE-2021-34261?

The vulnerability in USBH_ParseCfgDesc() of STMicroelectronics STM32Cube Middleware v1.8.0 and below triggers a denial of service due to system freeze while configuring remote wake-up functionality.

The Impact of CVE-2021-34261

The impact of CVE-2021-34261 is the unavailability of the system caused by hanging when configuring remote wake-up, leading to a denial of service situation.

Technical Details of CVE-2021-34261

The technical aspects of CVE-2021-34261 include vulnerability description, affected systems and versions, and exploitation mechanism.

Vulnerability Description

The vulnerability arises in USBH_ParseCfgDesc() in STMicroelectronics STM32Cube Middleware v1.8.0 and below, causing a system hang during configuration of remote wake-up.

Affected Systems and Versions

STMicroelectronics STM32Cube Middleware v1.8.0 and earlier versions are affected by this vulnerability, impacting systems that employ USB functions.

Exploitation Mechanism

The vulnerability is exploited by malicious actors configuring remote wake-up in the system, triggering a hang that disrupts normal system operation.

Mitigation and Prevention

Understanding the steps to take immediately and implementing long-term security practices can help mitigate the risk posed by CVE-2021-34261.

Immediate Steps to Take

Immediate mitigation steps include monitoring system behavior, restricting USB functionality, and applying vendor patches if available.

Long-Term Security Practices

Implementing secure coding practices, keeping middleware components updated, and monitoring for future vulnerabilities are key long-term security measures.

Patching and Updates

Vendor-supplied patches addressing the vulnerability in USBH_ParseCfgDesc() should be applied promptly to secure systems against potential denial of service attacks.