# CVE-2025-5820: Sony XAV-AX8500 Bluetooth ERTM Channel Authentication Bypass Vulnerability

> Network-adjacent attackers can bypass authentication on Sony XAV-AX8500 devices due to improper Bluetooth ERTM channel initialization.

- **Severity:** Medium 6.3 (`CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L`)
- **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:** 21 Jun 2025
- **Updated:** 23 Jun 2025
- **Also known as:** GHSA-m84m-25cj-px8x

## What is CVE-2025-5820?

CVE-2025-5820 is a medium-severity authentication bypass vulnerability in Sony XAV-AX8500, published on 21 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Sony XAV-AX8500 Bluetooth ERTM Channel Authentication Bypass Vulnerability. This vulnerability allows network-adjacent attackers to bypass authentication on affected Sony XAV-AX8500 devices. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the implementation of Bluetooth ERTM channel communication. The issue results from improper channel data initialization. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-26285.

Weakness: CWE-288 (Authentication Bypass Using an Alternate Path or Channel)

## Which versions are affected by CVE-2025-5820?

It affects 1 product.


Products: Sony Xav-Ax8500 Firmware.

## How do I fix CVE-2025-5820?

No fix has been published for CVE-2025-5820 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-5820 being exploited?

There is no known exploitation of CVE-2025-5820 in the wild and no public exploit code.

## Other vulnerabilities in Sony XAV-AX8500

- [CVE-2025-5478](https://insights.sbomify.com/CVE-2025-5478/): Sony XAV-AX8500 Bluetooth SDP Protocol Integer Overflow Remote Code Execution Vulnerability (high 8.8)
- [CVE-2025-5475](https://insights.sbomify.com/CVE-2025-5475/): Sony XAV-AX8500 Bluetooth Packet Handling Integer Overflow Remote Code Execution Vulnerability (high 7.5)
- [CVE-2025-5477](https://insights.sbomify.com/CVE-2025-5477/): Sony XAV-AX8500 Bluetooth L2CAP Protocol Heap-based Buffer Overflow Remote Code Execution Vulnerability (high 7.5)
- [CVE-2025-5479](https://insights.sbomify.com/CVE-2025-5479/): Sony XAV-AX8500 Bluetooth AVCTP Protocol Heap-based Buffer Overflow Remote Code Execution Vulnerability (high 7.5)
- [CVE-2025-5476](https://insights.sbomify.com/CVE-2025-5476/): Sony XAV-AX8500 Bluetooth Improper Isolation Authentication Bypass Vulnerability (medium 6.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-5820 and fix it if it is affected.

What it is: CVE-2025-5820 is a medium-severity authentication bypass vulnerability in Sony XAV-AX8500, published on 21 Jun 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-2025-5820 in the wild and no public exploit code.

Affected product: Sony XAV-AX8500. 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-2025-5820/ (Markdown: https://insights.sbomify.com/CVE-2025-5820/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-5820
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-5820
- OSV: https://osv.dev/vulnerability/CVE-2025-5820

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-5820/
Summaries are generated and may contain mistakes; the official description above is the record.