# CVE-2019-18939: Command injection in n/a

> Unauthenticated attackers can execute arbitrary TCL scripts via HTTP POST requests to specific CGI scripts in Homematic CCU devices with the HM-Print AddOn installed.

- **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:** 14 Nov 2019
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-rgpm-vm97-966x

## What is CVE-2019-18939?

CVE-2019-18939 is a critical command injection vulnerability in n/a, published on 14 Nov 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

eQ-3 Homematic CCU2 2.47.20 and CCU3 3.47.18 with the HM-Print AddOn through 1.2a installed allow Remote Code Execution by unauthenticated attackers with access to the web interface via the exec.cgi and exec1.cgi scripts, which execute TCL script content from an HTTP POST request.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2019-18939?

It affects 3 products.


Products: Eq-3 Homematic Ccu2 Firmware, Eq-3 Homematic Ccu3 Firmware, Hm-Print Project Hm-Print.

## How do I fix CVE-2019-18939?

No fix has been published for CVE-2019-18939 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-18939 being exploited?

There is no known exploitation of CVE-2019-18939 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-33032](https://insights.sbomify.com/CVE-2021-33032/): Command injection in n/a (critical 10.0)
- [CVE-2019-18937](https://insights.sbomify.com/CVE-2019-18937/): Command injection in n/a (critical 9.8)
- [CVE-2019-18938](https://insights.sbomify.com/CVE-2019-18938/): Code injection in n/a (critical 9.8)
- [CVE-2019-16199](https://insights.sbomify.com/CVE-2019-16199/): Auth bypass in n/a (critical 9.8)
- [CVE-2019-9584](https://insights.sbomify.com/CVE-2019-9584/): Missing authorization in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-18939 and fix it if it is affected.

What it is: CVE-2019-18939 is a critical command injection vulnerability in n/a, published on 14 Nov 2019. 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-2019-18939 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-2019-18939/ (Markdown: https://insights.sbomify.com/CVE-2019-18939/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-18939
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-18939
- OSV: https://osv.dev/vulnerability/CVE-2019-18939

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-18939/
Summaries are generated and may contain mistakes; the official description above is the record.