# CVE-2023-3596: Rockwell Automation Allen-Bradley ControlLogix Communication Modules vulnerable to Denial of Service

> A malicious user can cause a denial of service on Rockwell Automation ControlLogix communication modules by sending crafted CIP messages.

- **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 Jul 2023
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-xvq9-c88q-jf5x

## What is CVE-2023-3596?

CVE-2023-3596 is a high-severity denial of service vulnerability in Rockwell Automation 1756-EN4TR Series A, published on 12 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Where this vulnerability exists in the Rockwell Automation 1756-EN4* Ethernet/IP communication products, it could allow a malicious user to cause a denial of service by asserting the target system through maliciously crafted CIP messages.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2023-3596?

It affects 3 products.


Products: Rockwellautomation 1756-En4tr Firmware, Rockwellautomation 1756-En4trk Firmware, Rockwellautomation 1756-En4trxt Firmware.

## How do I fix CVE-2023-3596?

No fix has been published for CVE-2023-3596 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-3596 being exploited?

There is no known exploitation of CVE-2023-3596 in the wild and no public exploit code.

## Other vulnerabilities in Rockwell Automation 1756-EN4TR Series A

- [CVE-2024-8626](https://insights.sbomify.com/CVE-2024-8626/): Logix Controllers Vulnerable to Denial-of-Service Vulnerability (high 8.7)
- [CVE-2024-3493](https://insights.sbomify.com/CVE-2024-3493/): Rockwell Automation ControlLogix and GaurdLogix Vulnerable to Major Nonrecoverable Fault Due to Invalid Header Value (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-3596 and fix it if it is affected.

What it is: CVE-2023-3596 is a high-severity denial of service vulnerability in Rockwell Automation 1756-EN4TR Series A, published on 12 Jul 2023. 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-2023-3596 in the wild and no public exploit code.

Affected product: Rockwell Automation 1756-EN4TR Series 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-2023-3596/ (Markdown: https://insights.sbomify.com/CVE-2023-3596/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-3596
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-3596
- OSV: https://osv.dev/vulnerability/CVE-2023-3596

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-3596/
Summaries are generated and may contain mistakes; the official description above is the record.