PatchTheCVECVE-2021-34145: The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 devices does n
CVE-2021-34145 is a medium-severity flaw (CVSS 5.3) affecting wireless internet connectivity for embedded devices. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 devices does not properly handle the reception of LMP_max_slot with an invalid Baseband packet type (and LT_ADDRESS and LT_ADDR) after completion of the LMP setup procedure, allowing attackers in radio range to trigger a denial of service (firmware crash) via a crafted LMP packet.
Why this priority
- No elevated risk signals yet
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Adjacent network |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 56%) |
| CISA exploited list | No |
| Published | 2021-09-07 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
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-2021-34145?
wireless internet connectivity for embedded devices: upgrade to newer than 2.9.0. Exact commands for each OS are on this page.
Is CVE-2021-34145 being exploited?
CVE-2021-34145 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-2021-34145 affect?
CVE-2021-34145 affects wireless internet connectivity for embedded devices. Severity is medium (CVSS 5.3). The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 devices does not properly handle the reception of LMP_max_slot with an invalid Baseband packet type (and LT_ADDRESS and LT_ADDR) after completio
How urgent is CVE-2021-34145?
Priority 29/100. No elevated risk signals yet.
Software pages
Related CVEs
- CVE-2021-34148 MEDIUM 6.5 UPGRADE The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 devices does n
- CVE-2021-34147 MEDIUM 6.5 UPGRADE The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 does not prope