# CVE-2020-15796: Denial of service in SIMATIC ET 200SP Open Controller (incl. SIPLUS variants)

> Remote attackers can cause denial of service on Siemens SIMATIC controllers by sending crafted HTTP requests to the web server.

- **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:** 14 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-mffw-j524-mrjp

## What is CVE-2020-15796?

CVE-2020-15796 is a high-severity denial of service vulnerability in Siemens SIMATIC ET 200SP Open Controller (incl. SIPLUS variants), published on 14 Dec 2020. 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 ET 200SP Open Controller (incl. SIPLUS variants) (V20.8), SIMATIC S7-1500 Software Controller (V20.8). The web server of the affected products contains a vulnerability that could allow a remote attacker to trigger a denial-of-service condition by sending a specially crafted HTTP request.

Weakness: CWE-248 (Uncaught Exception)

## Which versions are affected by CVE-2020-15796?

It affects 2 products.


Products: Siemens Simatic Et 200sp Open Controller Firmware, Siemens Simatic S7-1500 Software Controller Firmware.

## How do I fix CVE-2020-15796?

No fix has been published for CVE-2020-15796 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-15796 being exploited?

There is no known exploitation of CVE-2020-15796 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-15796 and fix it if it is affected.

What it is: CVE-2020-15796 is a high-severity denial of service vulnerability in Siemens SIMATIC ET 200SP Open Controller (incl. SIPLUS variants), published on 14 Dec 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-2020-15796 in the wild and no public exploit code.

Affected product: Siemens SIMATIC ET 200SP Open Controller (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-2020-15796/ (Markdown: https://insights.sbomify.com/CVE-2020-15796/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-15796
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-15796
- OSV: https://osv.dev/vulnerability/CVE-2020-15796

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-15796/
Summaries are generated and may contain mistakes; the official description above is the record.