# CVE-2024-3721: TBK DVR-4104/DVR-4216 os command injection

> Remote attackers can execute arbitrary OS commands on TBK DVR devices via the mdb/mdc parameter in device.rsp.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Apr 2024
- **Updated:** 1 Aug 2024
- **Also known as:** GHSA-795f-8w3g-5h2q

## What is CVE-2024-3721?

CVE-2024-3721 is a medium-severity command injection vulnerability in TBK DVR-4104, published on 13 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was found in TBK DVR-4104 and DVR-4216 up to 20240412 and classified as critical. This issue affects some unknown processing of the file /device.rsp?opt=sys&cmd=___S_O_S_T_R_E_A_MAX___. The manipulation of the argument mdb/mdc leads to os command injection. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The identifier VDB-260573 was assigned to this vulnerability.

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

## Which versions are affected by CVE-2024-3721?


## How do I fix CVE-2024-3721?

No fix has been published for CVE-2024-3721 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-3721 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-3721 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-3721 and fix it if it is affected.

What it is: CVE-2024-3721 is a medium-severity command injection vulnerability in TBK DVR-4104, published on 13 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-3721 exists.

Affected product: TBK DVR-4104. 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-2024-3721/ (Markdown: https://insights.sbomify.com/CVE-2024-3721/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-3721
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-3721
- OSV: https://osv.dev/vulnerability/CVE-2024-3721

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-3721/
Summaries are generated and may contain mistakes; the official description above is the record.