# CVE-2021-33016: KUKA KR C4 - Use of Hard-Coded Credentials

> Attackers can gain full access to sensitive folders in KUKA KR C4 control software due to hard-coded credentials, requiring an upgrade to mitigate.

- **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:** 26 May 2022
- **Updated:** 16 Apr 2025
- **Also known as:** GHSA-pf82-6f4p-5p6c

## What is CVE-2021-33016?

CVE-2021-33016 is a critical vulnerability in KUKA KR C4, published on 26 May 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An attacker can gain full access (read/write/delete) to sensitive folders due to hard-coded credentials on KUKA KR C4 control software for versions prior to 8.7 or any product running KSS.

Weakness: CWE-798 (Use of Hard-coded Credentials)

## Which versions are affected by CVE-2021-33016?

It affects 2 products.


Products: Kuka Kr C4 Firmware, Kuka Kss.

## How do I fix CVE-2021-33016?

No fix has been published for CVE-2021-33016 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-33016 being exploited?

There is no known exploitation of CVE-2021-33016 in the wild and no public exploit code.

## Other vulnerabilities in KUKA KR C4

- [CVE-2021-33014](https://insights.sbomify.com/CVE-2021-33014/): KUKA KR C4 - Use of Hard-Coded Credentials (high 8.8)
- [CVE-2020-10268](https://insights.sbomify.com/CVE-2020-10268/): RVD#2550: Terminate Critical Services in KUKA controller KR C4 (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-33016 and fix it if it is affected.

What it is: CVE-2021-33016 is a critical vulnerability in KUKA KR C4, published on 26 May 2022. 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-2021-33016 in the wild and no public exploit code.

Affected product: KUKA KR C4. 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-2021-33016/ (Markdown: https://insights.sbomify.com/CVE-2021-33016/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-33016
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-33016
- OSV: https://osv.dev/vulnerability/CVE-2021-33016

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-33016/
Summaries are generated and may contain mistakes; the official description above is the record.