# CVE-2021-34145: Denial of service in n/a

> Attackers in radio range can crash Cypress Bluetooth devices by sending crafted LMP packets, causing a denial of service.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Sep 2021
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2021-34145, GHSA-7j4h-6cq9-gmjv, UBUNTU-CVE-2021-34145

## What is CVE-2021-34145?

CVE-2021-34145 is a medium-severity denial of service vulnerability in n/a, published on 7 Sep 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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.

## Which versions are affected by CVE-2021-34145?

It affects 1 product.


Products: Cypress Wireless Internet Connectivity for Embedded Devices.

## How do I fix CVE-2021-34145?

Upgrade to a fixed version.

## Is CVE-2021-34145 being exploited?

There is no known exploitation of CVE-2021-34145 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-34147](https://insights.sbomify.com/CVE-2021-34147/): Denial of service in n/a (medium 6.5)
- [CVE-2021-34148](https://insights.sbomify.com/CVE-2021-34148/): Denial of service in n/a (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34145 and fix it if it is affected.

What it is: CVE-2021-34145 is a medium-severity denial of service vulnerability in n/a, published on 7 Sep 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-34145 in the wild and no public exploit code.

Affected product: n/a. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2021-34145/ (Markdown: https://insights.sbomify.com/CVE-2021-34145/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34145
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34145
- OSV: https://osv.dev/vulnerability/CVE-2021-34145

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-34145/
Summaries are generated and may contain mistakes; the official description above is the record.