# CVE-2021-20997: WAGO: Managed Switches: Unauthorized access to password hashes

> Attackers can read password hashes of all web-based management users on WAGO managed switches, potentially leading to credential compromise.

- **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:** 13 May 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-9w62-6mhp-433w

## What is CVE-2021-20997?

CVE-2021-20997 is a high-severity vulnerability in WAGO 0852-0303, published on 13 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In multiple managed switches by WAGO in different versions it is possible to read out the password hashes of all Web-based Management users.

Weakness: CWE-522 (Insufficiently Protected Credentials)

## Which versions are affected by CVE-2021-20997?

It affects 5 products.


Products: Wago 0852-0303 Firmware, Wago 0852-1305\/000-001 Firmware, Wago 0852-1305 Firmware, Wago 0852-1505\/000-001 Firmware, Wago 0852-1505 Firmware.

## How do I fix CVE-2021-20997?

No fix has been published for CVE-2021-20997 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20997 being exploited?

There is no known exploitation of CVE-2021-20997 in the wild and no public exploit code.

## Other vulnerabilities in WAGO 0852-0303

- [CVE-2021-20998](https://insights.sbomify.com/CVE-2021-20998/): WAGO: Managed Switches: Unauthorized creation of user accounts (critical 10.0)
- [CVE-2021-20994](https://insights.sbomify.com/CVE-2021-20994/): WAGO: Managed Switches: Reflected Cross-site Scripting (high 8.8)
- [CVE-2021-20993](https://insights.sbomify.com/CVE-2021-20993/): WAGO: Managed Switches: Exposure of sensitive information through directory listing (medium 5.3)
- [CVE-2021-20995](https://insights.sbomify.com/CVE-2021-20995/): WAGO: Managed Switches: Storage of user credentials in a cookie (medium 5.3)
- [CVE-2021-20996](https://insights.sbomify.com/CVE-2021-20996/): WAGO: Managed Switches: Unsecure Cookie settings (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20997 and fix it if it is affected.

What it is: CVE-2021-20997 is a high-severity vulnerability in WAGO 0852-0303, published on 13 May 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-2021-20997 in the wild and no public exploit code.

Affected product: WAGO 0852-0303. 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-2021-20997/ (Markdown: https://insights.sbomify.com/CVE-2021-20997/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20997
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20997
- OSV: https://osv.dev/vulnerability/CVE-2021-20997

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20997/
Summaries are generated and may contain mistakes; the official description above is the record.