# CVE-2023-3373: Information disclosure in GOT SIMPLE Series GS21 model

> Remote attackers can hijack data sessions or cause denial of service by predicting FTP listening ports on Mitsubishi Electric HMI devices.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 3 Aug 2023
- **Updated:** 27 Feb 2025
- **Also known as:** GHSA-5gwv-ww26-4rhf

## What is CVE-2023-3373?

CVE-2023-3373 is a medium-severity vulnerability in Mitsubishi Electric Corporation GOT SIMPLE Series GS21 model, published on 3 Aug 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Predictable Exact Value from Previous Values vulnerability in Mitsubishi Electric Corporation GOT2000 Series GT21 model versions 01.49.000 and prior and GOT SIMPLE Series GS21 model versions 01.49.000 and prior allows a remote unauthenticated attacker to hijack data connections (session hijacking) or prevent legitimate users from establishing data connections (to cause DoS condition) by guessing the listening port of the data connection on FTP server and connecting to it.

Weakness: CWE-330 (Use of Insufficiently Random Values), CWE-342 (Predictable Exact Value from Previous Values)

## Which versions are affected by CVE-2023-3373?

It affects 2 products.


Products: Mitsubishielectric Gs21 Firmware, Mitsubishielectric Gt21 Firmware.

## How do I fix CVE-2023-3373?

No fix has been published for CVE-2023-3373 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-3373 being exploited?

There is no known exploitation of CVE-2023-3373 in the wild and no public exploit code.

## Other vulnerabilities in Mitsubishi Electric Corporation GOT SIMPLE Series GS21 model

- [CVE-2023-0525](https://insights.sbomify.com/CVE-2023-0525/): Weak cryptography in GOT SIMPLE Series GS21 model (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-3373 and fix it if it is affected.

What it is: CVE-2023-3373 is a medium-severity vulnerability in Mitsubishi Electric Corporation GOT SIMPLE Series GS21 model, published on 3 Aug 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2023-3373 in the wild and no public exploit code.

Affected product: Mitsubishi Electric Corporation GOT SIMPLE Series GS21 model. 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-2023-3373/ (Markdown: https://insights.sbomify.com/CVE-2023-3373/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-3373
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-3373
- OSV: https://osv.dev/vulnerability/CVE-2023-3373

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-3373/
Summaries are generated and may contain mistakes; the official description above is the record.