CVE-2021-38545 : What You Need to Know
Discover the impact of CVE-2021-38545, a vulnerability in Raspberry Pi 3 B+ and 4 B devices that enables remote attackers to recover speech signals via a telescope and an electro-optical sensor.
A vulnerability has been identified in Raspberry Pi 3 B+ and 4 B devices that allows remote attackers to recover speech signals from an LED on the device in specific use cases. This exploit, known as the "Glowworm" attack, involves utilizing a telescope and an electro-optical sensor to analyze light intensity variations.
Understanding CVE-2021-38545
This section provides detailed insights into the nature of the vulnerability and its potential impact.
What is CVE-2021-38545?
The vulnerability in Raspberry Pi devices allows attackers to recover speech signals by analyzing variations in the power indicator LED's light intensity caused by the power consumption fluctuations associated with audio output equipment.
The Impact of CVE-2021-38545
By exploiting this vulnerability, remote attackers can eavesdrop on audio signals played through connected speakers by capturing light variations from the Raspberry Pi's power indicator LED.
Technical Details of CVE-2021-38545
This section delves into the technical aspects of the CVE, including the vulnerability description, affected systems, and the exploitation mechanism.
Vulnerability Description
The vulnerability stems from a direct connection between the power indicator LED and the power line on Raspberry Pi devices, allowing for the recovery of audio signals based on light intensity fluctuations.
Affected Systems and Versions
Raspberry Pi 3 B+ and 4 B devices are affected through August 9, 2021, in scenarios where the device powers audio-output equipment.
Exploitation Mechanism
Attackers can recover speech signals by analyzing measurements captured from an electro-optical sensor pointed at the power indicator LED of the Raspberry Pi.
Mitigation and Prevention
This section outlines steps to mitigate the risks associated with CVE-2021-38545 and prevent potential exploitation.
Immediate Steps to Take
Users should disconnect power to audio equipment from Raspberry Pi devices if concerned about potential eavesdropping.
Long-Term Security Practices
Implementing physical security measures to prevent unauthorized access to Raspberry Pi devices can enhance long-term security.
Patching and Updates
Monitor official Raspberry Pi channels for any security patches or updates that address this vulnerability.