CVE-2021-28155: The Bluetooth Classic implementation on JBL TUNE500BT devices does not properly handle the reception of contin

Routine

MEDIUM 6.5MITIGATE

CVE-2021-28155 is a medium-severity flaw (CVSS 6.5) affecting tune500bt firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The Bluetooth Classic implementation on JBL TUNE500BT devices does not properly handle the reception of continuous unsolicited LMP responses, allowing attackers in radio range to trigger a denial of service and shutdown a device by flooding the target device with LMP Feature Response data.

Why this priority

No elevated risk signals yet

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Adjacent network
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 61%)
CISA exploited list	No
Published	2021-09-07
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: jbl

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-09-07 06:15 UTCPublished CVE record published
2026-06-17 03:45 UTCUpdated Record last modified

jbl tune500bt firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-28155?

tune500bt firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-28155 being exploited?

CVE-2021-28155 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-28155 affect?

CVE-2021-28155 affects tune500bt firmware. Severity is medium (CVSS 6.5). The Bluetooth Classic implementation on JBL TUNE500BT devices does not properly handle the reception of continuous unsolicited LMP responses, allowing attackers in radio range to trigger a denial of service and shutdown a device by flooding

How urgent is CVE-2021-28155?

Priority 33/100. No elevated risk signals yet.

Software pages

Bluetooth vulnerabilities

References

← Back to latest CVEs