# CVE-2020-2509: QNAP Network-Attached Storage (NAS) Command Injection

> Attackers can execute arbitrary commands on QNAP NAS devices running QTS or QuTS hero, requiring an upgrade to patched firmware versions.

- **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:** Yes, since 11 Apr 2022 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Apr 2021
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-77jf-5mcg-g6m9

## What is CVE-2020-2509?

CVE-2020-2509 is a critical command injection vulnerability in Qnap Qts, published on 17 Apr 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A command injection vulnerability has been reported to affect QTS and QuTS hero. If exploited, this vulnerability allows attackers to execute arbitrary commands in a compromised application. We have already fixed this vulnerability in the following versions: QTS 4.5.2.1566 Build 20210202 and later QTS 4.5.1.1495 Build 20201123 and later QTS 4.3.6.1620 Build 20210322 and later QTS 4.3.4.1632 Build 20210324 and later QTS 4.3.3.1624 Build 20210416 and later QTS 4.2.6 Build 20210327 and later QuTS hero h4.5.1.1491 build 20201119 and later

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

## Which versions are affected by CVE-2020-2509?

It affects 2 products.


Products: Qnap Qts, Qnap Quts Hero.

## How do I fix CVE-2020-2509?

No fix has been published for CVE-2020-2509 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 2 May 2022.

## Is CVE-2020-2509 being exploited?

Yes. Attackers have exploited CVE-2020-2509 in the wild since at least 11 Apr 2022.

Public exploit code:

- QNAP N-Day (Probably not CVE-2020-2509) (github_poc): https://github.com/jbaines-r7/overkill

## Other vulnerabilities in Qnap Qts

- [CVE-2018-19949](https://insights.sbomify.com/CVE-2018-19949/): QNAP NAS File Station Command Injection (critical 9.8, exploited in the wild)
- [CVE-2019-7193](https://insights.sbomify.com/CVE-2019-7193/): QNAP QTS Improper Input Validation (critical 9.8, exploited in the wild)
- [CVE-2018-19943](https://insights.sbomify.com/CVE-2018-19943/): QNAP NAS File Station Cross-Site Scripting (high 8.0, exploited in the wild)
- [CVE-2018-19953](https://insights.sbomify.com/CVE-2018-19953/): QNAP NAS File Station Cross-Site Scripting (medium 6.1, exploited in the wild)
- [CVE-2024-32766](https://insights.sbomify.com/CVE-2024-32766/): QTS, QuTS hero, QuTScloud (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-2509 and fix it if it is affected.

What it is: CVE-2020-2509 is a critical command injection vulnerability in Qnap Qts, published on 17 Apr 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2020-2509 in the wild since at least 11 Apr 2022.

Affected product: Qnap Qts. 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-2020-2509/ (Markdown: https://insights.sbomify.com/CVE-2020-2509/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-2509
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-2509
- OSV: https://osv.dev/vulnerability/CVE-2020-2509

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-2509/
Summaries are generated and may contain mistakes; the official description above is the record.