# CVE-2021-38395: Honeywell Experion PKS and ACE Controllers Injection

> Attackers can remotely execute arbitrary code and cause denial of service on Honeywell Experion PKS and ACE controllers via improper neutralization of special elements.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:** 28 Oct 2022
- **Updated:** 16 Apr 2025
- **Also known as:** GHSA-cqmh-9h94-59vr

## What is CVE-2021-38395?

CVE-2021-38395 is a critical code injection vulnerability in Honeywell Experion PKS, published on 28 Oct 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Honeywell Experion PKS C200, C200E, C300, and ACE controllers are vulnerable to improper neutralization of special elements in output, which may allow an attacker to remotely execute arbitrary code and cause a denial-of-service condition.

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

## Which versions are affected by CVE-2021-38395?

It affects 4 products.


Products: Honeywell Application Control Environment Firmware, Honeywell C200 Firmware, Honeywell C200e Firmware, Honeywell C300 Firmware.

## How do I fix CVE-2021-38395?

No fix has been published for CVE-2021-38395 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-38395 being exploited?

There is no known exploitation of CVE-2021-38395 in the wild and no public exploit code.

## Other vulnerabilities in Honeywell Experion PKS

- [CVE-2021-38397](https://insights.sbomify.com/CVE-2021-38397/): Honeywell Experion PKS and ACE Controllers Unrestricted Upload of File with Dangerous Type (critical 10.0)
- [CVE-2021-38399](https://insights.sbomify.com/CVE-2021-38399/): Honeywell Experion PKS and ACE Controllers Relative Path Traversal (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-38395 and fix it if it is affected.

What it is: CVE-2021-38395 is a critical code injection vulnerability in Honeywell Experion PKS, published on 28 Oct 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-2021-38395 in the wild and no public exploit code.

Affected product: Honeywell Experion PKS. 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-2021-38395/ (Markdown: https://insights.sbomify.com/CVE-2021-38395/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-38395
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-38395
- OSV: https://osv.dev/vulnerability/CVE-2021-38395

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-38395/
Summaries are generated and may contain mistakes; the official description above is the record.