# CVE-2020-25242: Denial of service in SIMATIC NET CP 343-1 Advanced (incl. SIPLUS variants)

> Attackers can cause a denial-of-service condition on Siemens SIMATIC NET CP devices by sending specially crafted packets to TCP port 102.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:** 12 May 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-73pj-g97w-qp62

## What is CVE-2020-25242?

CVE-2020-25242 is a high-severity denial of service vulnerability in Siemens SIMATIC NET CP 343-1 Advanced (incl. SIPLUS variants), published on 12 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability has been identified in SIMATIC NET CP 343-1 Advanced (incl. SIPLUS variants) (All versions), SIMATIC NET CP 343-1 Lean (incl. SIPLUS variants) (All versions), SIMATIC NET CP 343-1 Standard (incl. SIPLUS variants) (All versions). Specially crafted packets sent to TCP port 102 could cause a Denial-of-Service condition on the affected devices. A cold restart might be necessary in order to recover.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2020-25242?

It affects 3 products.


Products: Siemens Simatic Net Cp 343-1 Advanced Firmware, Siemens Simatic Net Cp 343-1 Lean Firmware, Siemens Simatic Net Cp 343-1 Standard Firmware.

## How do I fix CVE-2020-25242?

No fix has been published for CVE-2020-25242 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-25242 being exploited?

There is no known exploitation of CVE-2020-25242 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-25242 and fix it if it is affected.

What it is: CVE-2020-25242 is a high-severity denial of service vulnerability in Siemens SIMATIC NET CP 343-1 Advanced (incl. SIPLUS variants), published on 12 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-2020-25242 in the wild and no public exploit code.

Affected product: Siemens SIMATIC NET CP 343-1 Advanced (incl. SIPLUS variants). 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-2020-25242/ (Markdown: https://insights.sbomify.com/CVE-2020-25242/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-25242
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-25242
- OSV: https://osv.dev/vulnerability/CVE-2020-25242

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-25242/
Summaries are generated and may contain mistakes; the official description above is the record.