CVE-2021-38548

CVE-2021-38548 is a medium-severity vulnerability in Jbl Go 2 Firmware with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

JBL Go 2 devices 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.

Frequently asked questions

What is CVE-2021-38548?
JBL Go 2 devices 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.
How severe is CVE-2021-38548?
CVE-2021-38548 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-38548 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38548?
CVE-2021-38548 affects Jbl Go 2 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-38548?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38548 published?
CVE-2021-38548 was published on 2021-08-11 and last updated on 2026-06-17.

References

Affected products (1)