# CVE-2021-38684: Buffer Overflow Vulnerability in Multimedia Console

> A stack buffer overflow in QNAP Multimedia Console allows attackers to execute arbitrary code on affected NAS devices.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/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:** 13 Nov 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-r9m4-448x-8fg7

## What is CVE-2021-38684?

CVE-2021-38684 is a high-severity memory corruption vulnerability in QNAP Systems Inc. Multimedia Console, published on 13 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A stack buffer overflow vulnerability has been reported to affect QNAP NAS running Multimedia Console. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of Multimedia Console: Multimedia Console 1.4.3 ( 2021/10/05 ) and later Multimedia Console 1.5.3 ( 2021/10/05 ) and later

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2021-38684?

It affects 1 product.


Products: Qnap Multimedia Console.

## How do I fix CVE-2021-38684?

No fix has been published for CVE-2021-38684 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-38684 being exploited?

There is no known exploitation of CVE-2021-38684 in the wild and no public exploit code.

## Other vulnerabilities in QNAP Systems Inc. Multimedia Console

- [CVE-2023-23364](https://insights.sbomify.com/CVE-2023-23364/): Multimedia Console (high 8.1)
- [CVE-2020-2493](https://insights.sbomify.com/CVE-2020-2493/): Cross-site Scripting Vulnerability in Multimedia Console (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-38684 and fix it if it is affected.

What it is: CVE-2021-38684 is a high-severity memory corruption vulnerability in QNAP Systems Inc. Multimedia Console, published on 13 Nov 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-2021-38684 in the wild and no public exploit code.

Affected product: QNAP Systems Inc. Multimedia Console. 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-2021-38684/ (Markdown: https://insights.sbomify.com/CVE-2021-38684/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-38684
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-38684
- OSV: https://osv.dev/vulnerability/CVE-2021-38684

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-38684/
Summaries are generated and may contain mistakes; the official description above is the record.