# CVE-2021-42561: Command injection in n/a

> Attackers can execute arbitrary shell commands via unsanitized input in the Human plugin when activated.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 12 Jan 2022
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-3893-j6q6-whq8

## What is CVE-2021-42561?

CVE-2021-42561 is a high-severity command injection vulnerability in n/a, published on 12 Jan 2022. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue was discovered in CALDERA 2.8.1. When activated, the Human plugin passes the unsanitized name parameter to a python "os.system" function. This allows attackers to use shell metacharacters (e.g., backticks "``" or dollar parenthesis "$()" ) in order to escape the current command and execute arbitrary shell commands.

Weakness: CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2021-42561?

It affects 1 product.


Products: Mitre Caldera.

## How do I fix CVE-2021-42561?

No fix has been published for CVE-2021-42561 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-42561 being exploited?

There is no known exploitation of CVE-2021-42561 in the wild and no public exploit code.

Public exploit code:

- CVE-2021-42561: Command Injection via the Human Plugin in MITRE Caldera (github_poc): https://github.com/mbadanoiu/CVE-2021-42561

## Other vulnerabilities in n/a

- [CVE-2021-42559](https://insights.sbomify.com/CVE-2021-42559/): Command injection in n/a (high 8.8)
- [CVE-2021-42560](https://insights.sbomify.com/CVE-2021-42560/): An issue was discovered in CALDERA 2.9.0. (high 8.8)
- [CVE-2020-19907](https://insights.sbomify.com/CVE-2020-19907/): Command injection in n/a (high 8.8)
- [CVE-2021-42562](https://insights.sbomify.com/CVE-2021-42562/): Missing authorization in n/a (high 8.1)
- [CVE-2022-40605](https://insights.sbomify.com/CVE-2022-40605/): Cross-site scripting in n/a (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-42561 and fix it if it is affected.

What it is: CVE-2021-42561 is a high-severity command injection vulnerability in n/a, published on 12 Jan 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-42561 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-2021-42561/ (Markdown: https://insights.sbomify.com/CVE-2021-42561/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-42561
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-42561
- OSV: https://osv.dev/vulnerability/CVE-2021-42561

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-42561/
Summaries are generated and may contain mistakes; the official description above is the record.