# CVE-2020-12506: WAGO: Authentication Bypass Vulnerability in WAGO 750-36X and WAGO 750-8XX Versions <= FW03

> Attackers can modify device settings without authentication on vulnerable WAGO I/O controllers, requiring firmware updates to mitigate.

- **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:** 30 Sep 2020
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-8c2w-ph9m-jcmf

## What is CVE-2020-12506?

CVE-2020-12506 is a critical authentication bypass vulnerability in WAGO 750-362, published on 30 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper Authentication vulnerability in WAGO 750-8XX series with FW version <= FW03 allows an attacker to change the settings of the devices by sending specifically constructed requests without authentication This issue affects: WAGO 750-362, WAGO 750-363, WAGO 750-823, WAGO 750-832/xxx-xxx, WAGO 750-862, WAGO 750-891, WAGO 750-890/xxx-xxx in versions FW03 and prior versions.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2020-12506?

It affects 7 products.


Products: Wago 750-362 Firmware, Wago 750-363 Firmware, Wago 750-823 Firmware, Wago 750-832 Firmware, Wago 750-862 Firmware, Wago 750-890 Firmware, Wago 750-891 Firmware.

## How do I fix CVE-2020-12506?

No fix has been published for CVE-2020-12506 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-12506 being exploited?

There is no known exploitation of CVE-2020-12506 in the wild and no public exploit code.

## Other vulnerabilities in WAGO 750-362

- [CVE-2021-34578](https://insights.sbomify.com/CVE-2021-34578/): WAGO: Authentication Vulnerability in Web-Based Management (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-12506 and fix it if it is affected.

What it is: CVE-2020-12506 is a critical authentication bypass vulnerability in WAGO 750-362, published on 30 Sep 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-2020-12506 in the wild and no public exploit code.

Affected product: WAGO 750-362. 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-2020-12506/ (Markdown: https://insights.sbomify.com/CVE-2020-12506/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-12506
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-12506
- OSV: https://osv.dev/vulnerability/CVE-2020-12506

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-12506/
Summaries are generated and may contain mistakes; the official description above is the record.