# CVE-2021-20991: Fibaro Home Center Authenticated remote command execution

> Authenticated attackers can execute arbitrary commands as root on Fibaro Home Center devices via a command injection flaw.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Apr 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-2v74-gvxm-8wmq

## What is CVE-2021-20991?

CVE-2021-20991 is a critical command injection vulnerability in Fibaro Home Center, published on 19 Apr 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Fibaro Home Center 2 and Lite devices with firmware version 4.540 and older an authenticated user can run commands as root user using a command injection vulnerability.

Weakness: CWE-77 (Improper Neutralization of Special Elements used in a Command), CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2021-20991?

It affects 2 products.


Products: Fibaro Home Center 2 Firmware, Fibaro Home Center Lite Firmware.

## How do I fix CVE-2021-20991?

No fix has been published for CVE-2021-20991 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20991 being exploited?

There is no known exploitation of CVE-2021-20991 in the wild and no public exploit code.

## Other vulnerabilities in Fibaro Home Center

- [CVE-2021-20992](https://insights.sbomify.com/CVE-2021-20992/): Fibaro Home Center Unencrypted management interface (high 8.1)
- [CVE-2021-20990](https://insights.sbomify.com/CVE-2021-20990/): Fibaro Home Center Unauthenticated access to shutdown, reboot and reboot to recovery mode (high 7.5)
- [CVE-2021-20989](https://insights.sbomify.com/CVE-2021-20989/): Fibaro Home Center Insufficient remote access server authorization (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20991 and fix it if it is affected.

What it is: CVE-2021-20991 is a critical command injection vulnerability in Fibaro Home Center, published on 19 Apr 2021. 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-2021-20991 in the wild and no public exploit code.

Affected product: Fibaro Home Center. 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-2021-20991/ (Markdown: https://insights.sbomify.com/CVE-2021-20991/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20991
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20991
- OSV: https://osv.dev/vulnerability/CVE-2021-20991

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20991/
Summaries are generated and may contain mistakes; the official description above is the record.