CVE-2021-38549 : Exploit Details and Defense Strategies

A USB splitter vulnerability in MIRACASE MHUB500 devices enables remote attackers to recover speech signals using a Glowworm attack method.

Understanding CVE-2021-38549

This CVE refers to a security flaw in USB splitters that can be exploited by attackers to recover sound signals from connected speakers.

What is CVE-2021-38549?

The issue occurs in certain scenarios where the USB splitter powers audio-output equipment, allowing attackers to capture speech signals through an LED on the device.

The Impact of CVE-2021-38549

The vulnerability poses a serious risk as attackers can eavesdrop on conversations or extract sensitive information through the compromised USB splitter.

Technical Details of CVE-2021-38549

The vulnerability is related to the power consumption correlation with the intensity of the USB splitter's power indicator LED, which can be exploited to recover sound signals.

Vulnerability Description

By analyzing data from an electro-optical sensor aimed at the power indicator LED, attackers can reconstruct sound from the connected speakers.

Affected Systems and Versions

MIRACASE MHUB500 USB splitters are affected through August 9, allowing potential exploitation.

Exploitation Mechanism

The attack, known as a Glowworm attack, involves using a telescope and an electro-optical sensor to recover sound signals from the LED.

Mitigation and Prevention

It is essential to take immediate steps to address the CVE and implement long-term security practices.

Immediate Steps to Take

Ensure USB splitters are not powering sensitive audio equipment and monitor any suspicious activities related to power consumption.

Long-Term Security Practices

Regularly update firmware, conduct security assessments, and consider replacing vulnerable USB splitters with more secure alternatives.

Patching and Updates

Stay informed about patches released by the vendor and apply them promptly to mitigate the risk of exploitation.