# CVE-2011-3486: Denial of service in n/a

> Remote attackers can cause a denial of service in Beckhoff TwinCAT via a crafted UDP request, impacting industrial control systems.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 16 Sep 2011
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-74h6-2hgj-rvpx

## What is CVE-2011-3486?

CVE-2011-3486 is a medium-severity denial of service vulnerability in n/a, published on 16 Sep 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Beckhoff TwinCAT 2.11.0.2004 and earlier allows remote attackers to cause a denial of service via a crafted request to UDP port 48899, which triggers an out-of-bounds read.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2011-3486?

It affects 1 product.


Products: Beckhoff Twincat.

## How do I fix CVE-2011-3486?

No fix has been published for CVE-2011-3486 yet. Limit exposure of the affected software until one is available.

## Is CVE-2011-3486 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2011-3486 exists.

Public exploit code:

- Beckhoff TwinCAT SCADA PLC 2.11.0.2004 DoS (metasploit)
- Beckhoff TwinCAT 2.11.0.2004 - Denial of Service (exploitdb)

## Other vulnerabilities in n/a

- [CVE-2019-16871](https://insights.sbomify.com/CVE-2019-16871/): Auth bypass in n/a (critical 9.8)
- [CVE-2017-16726](https://insights.sbomify.com/CVE-2017-16726/): Weak cryptography in Beckhoff TwinCAT (critical 9.1)
- [CVE-2018-7502](https://insights.sbomify.com/CVE-2018-7502/): Privilege escalation in Beckhoff TwinCAT PLC products (high 7.8)
- [CVE-2019-5637](https://insights.sbomify.com/CVE-2019-5637/): Beckhoff TwinCAT Profinet Driver Divide-by-Zero Denial of Service (high 7.5)
- [CVE-2017-16718](https://insights.sbomify.com/CVE-2017-16718/): Weak cryptography in Beckhoff TwinCAT (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-3486 and fix it if it is affected.

What it is: CVE-2011-3486 is a medium-severity denial of service vulnerability in n/a, published on 16 Sep 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2011-3486 exists.

Affected product: n/a. 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-2011-3486/ (Markdown: https://insights.sbomify.com/CVE-2011-3486/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-3486
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-3486
- OSV: https://osv.dev/vulnerability/CVE-2011-3486

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From sbomify Insights: https://insights.sbomify.com/CVE-2011-3486/
Summaries are generated and may contain mistakes; the official description above is the record.