# CVE-2020-36517: Information disclosure in n/a

> A hardcoded DNS resolver configuration in Home Assistant OS allows attackers to leak internal network resource information.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Mar 2022
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-wj7x-544h-j3j3

## What is CVE-2020-36517?

CVE-2020-36517 is a high-severity vulnerability in n/a, published on 7 Mar 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An information leak in Nabu Casa Home Assistant Operating System and Home Assistant Supervised 2022.03 allows a DNS operator to gain knowledge about internal network resources via the hardcoded DNS resolver configuration.

Weakness: CWE-203 (Observable Discrepancy)

## Which versions are affected by CVE-2020-36517?

It affects 1 product.


Products: Home-Assistant Home-Assistant.

## How do I fix CVE-2020-36517?

No fix has been published for CVE-2020-36517 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-36517 being exploited?

There is no known exploitation of CVE-2020-36517 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2023-27482](https://insights.sbomify.com/CVE-2023-27482/): Auth bypass in core (critical 10.0)
- [CVE-2023-41895](https://insights.sbomify.com/CVE-2023-41895/): Cross-site Scripting via auth_callback login in Home Assistant Core (high 8.8)
- [CVE-2023-41897](https://insights.sbomify.com/CVE-2023-41897/): Lack of XFO header allows clickjacking in Home Assistant Core (high 8.8)
- [CVE-2026-54317](https://insights.sbomify.com/CVE-2026-54317/): Home Assistant: Konnected alarm-panel switch state and zone topology disclosed to unauthenticated actors on the LAN (high 7.6)
- [CVE-2018-21019](https://insights.sbomify.com/CVE-2018-21019/): Home Assistant information disclosure vulnerability (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-36517 and fix it if it is affected.

What it is: CVE-2020-36517 is a high-severity vulnerability in n/a, published on 7 Mar 2022. 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-2020-36517 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-2020-36517/ (Markdown: https://insights.sbomify.com/CVE-2020-36517/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-36517
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-36517
- OSV: https://osv.dev/vulnerability/CVE-2020-36517

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-36517/
Summaries are generated and may contain mistakes; the official description above is the record.