CVE-2021-38547: Medium severity Logitech Z120 Firmware vulnerability

Published Aug 11, 2021
·
Updated

Logitech Z120 and S120 speakers through 2021-08-09 allow remote attackers to recover speech signals from an LED on the device, via a telescope and an electro-optical sensor, aka a "Glowworm" attack. The power indicator LED of the speakers is connected directly to the power line, as a result, the intensity of a device's power indicator LED is correlative to the power consumption. The sound played by the speakers affects their power consumption and as a result is also correlative to the light intensity of the LEDs. By analyzing measurements obtained from an electro-optical sensor directed at the power indicator LEDs of the speakers, we can recover the sound played by them.

Affected Software

8 affected components
Logitech Z120 Firmware<=2021-08-09
Logitech Z120
Logitech S120 Firmware<=2021-08-09
Logitech S120
All of the following
Logitech Z120 Firmware<=2021-08-09
Logitech Z120
All of the following
Logitech S120 Firmware<=2021-08-09
Logitech S120

Event History

Aug 11, 2021
CVE Published
via MITRE·03:24 PM
Data Sourced
via MITRE·03:24 PM
Description
Data Sourced
via NVD·04:15 PM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-38547?

CVE-2021-38547 has been rated as a medium severity vulnerability due to the potential for remote attackers to recover speech signals.

2

How do I fix CVE-2021-38547?

To mitigate CVE-2021-38547, users should disconnect the vulnerable Logitech Z120 and S120 speakers, especially models with firmware versions up to inclusive of 2021-08-09.

3

Which devices are affected by CVE-2021-38547?

CVE-2021-38547 affects Logitech Z120 and S120 speakers with firmware versions up to 2021-08-09.

4

What kind of attack is described in CVE-2021-38547?

CVE-2021-38547 describes a 'Glowworm' attack where remote attackers can exploit the device's LED to recover audio signals.

5

Can the hardware of the Logitech Z120 and S120 be secured against CVE-2021-38547?

No, the hardware design itself makes the Logitech Z120 and S120 vulnerable to CVE-2021-38547, and software updates cannot resolve the underlying issue.

Contact

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