# CVE-2020-15802: Auth bypass in n/a

> Attackers can bypass Bluetooth authentication by overwriting existing bonds with unauthenticated keys, potentially taking over devices.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Sep 2020
- **Updated:** 4 Aug 2024
- **Also known as:** A-158854097, ASB-A-158854097, GHSA-2ffq-f4m4-q248, ROOT-OS-UBUNTU-2204-CVE-2020-15802, UBUNTU-CVE-2020-15802

## What is CVE-2020-15802?

CVE-2020-15802 is a medium-severity authentication bypass vulnerability in n/a, published on 11 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks, aka BLURtooth. Cross Transport Key Derivation in Bluetooth Core Specification v4.2 and v5.0 may permit an unauthenticated user to establish a bonding with one transport, either LE or BR/EDR, and replace a bonding already established on the opposing transport, BR/EDR or LE, potentially overwriting an authenticated key with an unauthenticated key, or a key with greater entropy with one with less.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2020-15802?

It affects 1 product.


Products: Bluetooth Bluetooth Core Specification.

## How do I fix CVE-2020-15802?

Apply the vendor's patch.

## Is CVE-2020-15802 being exploited?

There is no known exploitation of CVE-2020-15802 in the wild and no public exploit code.

Public exploit code:

- BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy [CVE-2020-15802] [CVE-2022-20361] (github_poc): https://github.com/francozappa/blur

## Other vulnerabilities in n/a

- [CVE-2022-25836](https://insights.sbomify.com/CVE-2022-25836/): Auth bypass in n/a (high 7.5)
- [CVE-2022-25837](https://insights.sbomify.com/CVE-2022-25837/): Auth bypass in n/a (high 7.5)
- [CVE-2020-26556](https://insights.sbomify.com/CVE-2020-26556/): Auth bypass in n/a (high 7.5)
- [CVE-2023-24023](https://insights.sbomify.com/CVE-2023-24023/): Weak cryptography in n/a (medium 6.4)
- [CVE-2020-26555](https://insights.sbomify.com/CVE-2020-26555/): Auth bypass in n/a (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-15802 and fix it if it is affected.

What it is: CVE-2020-15802 is a medium-severity authentication bypass vulnerability in n/a, published on 11 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-15802 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-2020-15802/ (Markdown: https://insights.sbomify.com/CVE-2020-15802/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-15802
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-15802
- OSV: https://osv.dev/vulnerability/CVE-2020-15802

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-15802/
Summaries are generated and may contain mistakes; the official description above is the record.