# CVE-2021-33191: MiNiFi CPP arbitrary script execution is possible on the agent's host machine through the c2 protocol

> Attackers can execute arbitrary scripts on the host machine via the c2 protocol's agent-update command, 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:** 24 Aug 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-h5f6-7m57-f2rg

## What is CVE-2021-33191?

CVE-2021-33191 is a critical command injection vulnerability in Apache NiFi - MiNiFi C++, published on 24 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

From Apache NiFi MiNiFi C++ version 0.5.0 the c2 protocol implements an "agent-update" command which was designed to patch the application binary. This "patching" command defaults to calling a trusted binary, but might be modified to an arbitrary value through a "c2-update" command. Said command is then executed using the same privileges as the application binary. This was addressed in version 0.10.0

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

## Which versions are affected by CVE-2021-33191?

It affects 1 product.


Products: Apache Nifi Minifi C\+\+.

## How do I fix CVE-2021-33191?

No fix has been published for CVE-2021-33191 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-33191 being exploited?

There is no known exploitation of CVE-2021-33191 in the wild and no public exploit code.

## Other vulnerabilities in Apache NiFi - MiNiFi C++

- [CVE-2023-41180](https://insights.sbomify.com/CVE-2023-41180/): Apache NiFi MiNiFi C++: Incorrect Certificate Validation in InvokeHTTP for MiNiFi C++ (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-33191 and fix it if it is affected.

What it is: CVE-2021-33191 is a critical command injection vulnerability in Apache NiFi - MiNiFi C++, published on 24 Aug 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-2021-33191 in the wild and no public exploit code.

Affected product: Apache NiFi - MiNiFi C++. 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-2021-33191/ (Markdown: https://insights.sbomify.com/CVE-2021-33191/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-33191
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-33191
- OSV: https://osv.dev/vulnerability/CVE-2021-33191

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-33191/
Summaries are generated and may contain mistakes; the official description above is the record.