# CVE-2019-5134: Auth bypass in WAGO PFC100 Firmware

> Attackers can bypass authentication filters in WAGO PFC controllers to disclose sensitive information via crafted requests.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Mar 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-5g96-3868-4x48

## What is CVE-2019-5134?

CVE-2019-5134 is a high-severity authentication bypass vulnerability in WAGO PFC100 Firmware, published on 10 Mar 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An exploitable regular expression without anchors vulnerability exists in the Web-Based Management (WBM) authentication functionality of WAGO PFC200 versions 03.00.39(12) and 03.01.07(13), and WAGO PFC100 version 03.00.39(12). A specially crafted authentication request can bypass regular expression filters, resulting in sensitive information disclosure.

## Which versions are affected by CVE-2019-5134?

It affects 2 products.


Products: Wago Pfc100 Firmware, Wago Pfc200 Firmware.

## How do I fix CVE-2019-5134?

No fix has been published for CVE-2019-5134 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-5134 being exploited?

There is no known exploitation of CVE-2019-5134 in the wild and no public exploit code.

## Other vulnerabilities in WAGO PFC100 Firmware

- [CVE-2019-5082](https://insights.sbomify.com/CVE-2019-5082/): Memory corruption in WAGO PFC100 (critical 9.8)
- [CVE-2019-5149](https://insights.sbomify.com/CVE-2019-5149/): Denial of service in WAGO PFC100 Firmware (high 7.5)
- [CVE-2019-5135](https://insights.sbomify.com/CVE-2019-5135/): Information disclosure in WAGO PFC100 Firmware (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-5134 and fix it if it is affected.

What it is: CVE-2019-5134 is a high-severity authentication bypass vulnerability in WAGO PFC100 Firmware, published on 10 Mar 2020. 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-2019-5134 in the wild and no public exploit code.

Affected product: WAGO PFC100 Firmware. 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-2019-5134/ (Markdown: https://insights.sbomify.com/CVE-2019-5134/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-5134
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-5134
- OSV: https://osv.dev/vulnerability/CVE-2019-5134

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-5134/
Summaries are generated and may contain mistakes; the official description above is the record.