Cyber Resilience

CVE-2021-38549

MediumPublic PoC

Published: 11 August 2021

Published
11 August 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0029 53.0th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-38549 is a medium-severity an unspecified weakness vulnerability in Benda Miracase Hmub500 Firmware. Its CVSS base score is 5.9 (Medium).

Operationally, ranked in the top 47.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

MIRACASE MHUB500 USB splitters through 2021-08-09, in certain specific use cases in which the device supplies power to audio-output equipment, allow remote attackers to recover speech signals from an LED on the device, via a telescope and an electro-optical sensor,…

more

aka a "Glowworm" attack. We assume that the USB splitter supplies power to some speakers. The power indicator LED of the USB splitter is connected directly to the power line, as a result, the intensity of the USB splitter's power indicator LED is correlative to its power consumption. The sound played by the connected speakers affects the USB splitter's power consumption and as a result is also correlative to the light intensity of the LED. By analyzing measurements obtained from an electro-optical sensor directed at the power indicator LED of the USB splitter, we can recover the sound played by the connected speakers.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

benda
miracase hmub500 firmware
≤ 2021-08-09

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References