# CVE-2019-5074: Memory corruption in WAGO PFC100

> Unauthenticated attackers can trigger a stack buffer overflow in the iocheckd service to execute arbitrary code on WAGO PFC controllers.

- **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:** 18 Dec 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-cc6m-vg7g-249c

## What is CVE-2019-5074?

CVE-2019-5074 is a critical memory corruption vulnerability in WAGO PFC100, published on 18 Dec 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An exploitable stack buffer overflow vulnerability exists in the iocheckd service ''I/O-Check'' functionality of WAGO PFC200 Firmware version 03.01.07(13), WAGO PFC200 Firmware version 03.00.39(12) and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause a stack buffer overflow, resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2019-5074?

It affects 2 products.


Products: Wago Pfc 100 Firmware, Wago Pfc 200 Firmware.

## How do I fix CVE-2019-5074?

No fix has been published for CVE-2019-5074 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-5074 being exploited?

There is no known exploitation of CVE-2019-5074 in the wild and no public exploit code.

## Other vulnerabilities in WAGO PFC100

- [CVE-2020-12522](https://insights.sbomify.com/CVE-2020-12522/): Command injection in Series PFC 100 (750-81xx/xxx-xxx) (critical 10.0)
- [CVE-2019-5075](https://insights.sbomify.com/CVE-2019-5075/): Memory corruption in WAGO PFC100 (critical 9.8)
- [CVE-2019-5079](https://insights.sbomify.com/CVE-2019-5079/): Memory corruption in WAGO PFC100 (critical 9.8)
- [CVE-2019-5081](https://insights.sbomify.com/CVE-2019-5081/): Memory corruption in WAGO PFC100 (critical 9.8)
- [CVE-2019-5077](https://insights.sbomify.com/CVE-2019-5077/): Denial of service in WAGO PFC100 (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-5074 and fix it if it is affected.

What it is: CVE-2019-5074 is a critical memory corruption vulnerability in WAGO PFC100, published on 18 Dec 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-2019-5074 in the wild and no public exploit code.

Affected product: WAGO PFC100. 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-2019-5074/ (Markdown: https://insights.sbomify.com/CVE-2019-5074/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-5074
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-5074
- OSV: https://osv.dev/vulnerability/CVE-2019-5074

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-5074/
Summaries are generated and may contain mistakes; the official description above is the record.