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.
Conclusion & alert: CVE-2021-28155 is rated Low Risk (35.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.10%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-01-05 | 0.25% | 0.10% | -0.15% |
| 2 | 2025-11-21 | 0.10% | 0.25% | +0.15% |
| 3 | 2025-11-18 | — | 0.10% | — |
Full EPSS history (9 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
2.8 | 3.6 | [email protected] |
| 6.1 | 2.0 | MEDIUM |
|
6.5 | 6.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| jbl | tune500bt_firmware | — | cpe:2.3:o:jbl:tune500bt_firmware:-:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://dl.packetstormsecurity.net/papers/general/braktooth.pdf | Technical Description Third Party Advisory |
| https://www.jbl.com.sg/over-ear-headphones/JBL+TUNE500BT.html | Product Vendor Advisory |