# CVE-2019-18269: Missing authorization in Omron PLC CJ Series

> Attackers can bypass access controls on Omron PLCs due to unrestricted external lock access, potentially compromising industrial control systems.

- **Severity:** High 8.6 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/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:** 16 Dec 2019
- **Updated:** 2 Jun 2026
- **Also known as:** GHSA-5xrh-m4jr-pgwp

## What is CVE-2019-18269?

CVE-2019-18269 is a high-severity missing authorization vulnerability in Omron PLC CJ Series, published on 16 Dec 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Omron’s CS and CJ series PLCs have an unrestricted externally accessible lock vulnerability.

Weakness: CWE-412 (Unrestricted Externally Accessible Lock)

## Which versions are affected by CVE-2019-18269?

It affects 2 products.


Products: Omron Plc Cj Firmware, Omron Plc Cs Firmware.

## How do I fix CVE-2019-18269?

No fix has been published for CVE-2019-18269 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-18269 being exploited?

There is no known exploitation of CVE-2019-18269 in the wild and no public exploit code.

## Other vulnerabilities in Omron PLC CJ Series

- [CVE-2019-18259](https://insights.sbomify.com/CVE-2019-18259/): Other in Omron PLC CJ and CS Series (critical 9.8)
- [CVE-2019-18261](https://insights.sbomify.com/CVE-2019-18261/): Auth bypass in Omron PLC CJ, CS and NJ Series (critical 9.8)
- [CVE-2019-13533](https://insights.sbomify.com/CVE-2019-13533/): Other in Omron PLC CJ and CS Series (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-18269 and fix it if it is affected.

What it is: CVE-2019-18269 is a high-severity missing authorization vulnerability in Omron PLC CJ Series, published on 16 Dec 2019. 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-2019-18269 in the wild and no public exploit code.

Affected product: Omron PLC CJ Series. 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-2019-18269/ (Markdown: https://insights.sbomify.com/CVE-2019-18269/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-18269
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-18269
- OSV: https://osv.dev/vulnerability/CVE-2019-18269

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-18269/
Summaries are generated and may contain mistakes; the official description above is the record.