# CVE-2025-3885: Harman Becker MGU21 Bluetooth Improper Input Validation Denial-of-Service Vulnerability

> Network-adjacent attackers can cause a denial-of-service condition on Harman Becker MGU21 devices via improper Bluetooth frame validation.

- **Severity:** Medium 5.3 (`CVSS:3.0/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:** No
- **Published:** 22 May 2025
- **Updated:** 22 May 2025
- **Also known as:** GHSA-c686-8f3m-h49h

## What is CVE-2025-3885?

CVE-2025-3885 is a medium-severity denial of service vulnerability in Harman Becker MGU21, published on 22 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Harman Becker MGU21 Bluetooth Improper Input Validation Denial-of-Service Vulnerability. This vulnerability allows network-adjacent attackers to create a denial-of-service condition on affected installations of Harman Becker MGU21 devices. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the Bluetooth stack of the BCM89359 chipset. The issue results from the lack of proper validation of Bluetooth frames. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-23942.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2025-3885?

It affects 1 product.


Products: Samsung Harman Mgu21 Firmware.

## How do I fix CVE-2025-3885?

No fix has been published for CVE-2025-3885 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-3885 being exploited?

There is no known exploitation of CVE-2025-3885 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-3885 and fix it if it is affected.

What it is: CVE-2025-3885 is a medium-severity denial of service vulnerability in Harman Becker MGU21, published on 22 May 2025. 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-2025-3885 in the wild and no public exploit code.

Affected product: Harman Becker MGU21. 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-2025-3885/ (Markdown: https://insights.sbomify.com/CVE-2025-3885/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-3885
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-3885
- OSV: https://osv.dev/vulnerability/CVE-2025-3885

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-3885/
Summaries are generated and may contain mistakes; the official description above is the record.