# CVE-2022-2081: Denial of service in RTU500 series CMU firmware

> An attacker can cause a denial of service by flooding the HCI Modbus TCP function, leading to a stack overflow and device reboot.

- **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:** 4 Jan 2024
- **Updated:** 22 May 2025
- **Also known as:** GHSA-v3xr-m742-g2v3

## What is CVE-2022-2081?

CVE-2022-2081 is a high-severity denial of service vulnerability in Hitachi Energy RTU500 series CMU firmware, published on 4 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability exists in the HCI Modbus TCP function included in the product versions listed above. If the HCI Modbus TCP is enabled and configured, an attacker could exploit the vulnerability by sending a specially crafted message to the RTU500 in a high rate, causing the targeted RTU500 CMU to reboot. The vulnerability is caused by a lack of flood control which eventually if exploited causes an internal stack overflow in the HCI Modbus TCP function.

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

## Which versions are affected by CVE-2022-2081?

It affects 4 products.


Products: Hitachienergy Rtu520 Firmware, Hitachienergy Rtu530 Firmware, Hitachienergy Rtu540 Firmware, Hitachienergy Rtu560 Firmware.

## How do I fix CVE-2022-2081?

No fix has been published for CVE-2022-2081 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-2081 being exploited?

There is no known exploitation of CVE-2022-2081 in the wild and no public exploit code.

## Other vulnerabilities in Hitachi Energy RTU500 series CMU firmware

- [CVE-2026-1773](https://insights.sbomify.com/CVE-2026-1773/): Denial of service in RTU500 series CMU firmware (high 8.7)
- [CVE-2023-5767](https://insights.sbomify.com/CVE-2023-5767/): Cross-site scripting in RTU500 (medium 6.0)
- [CVE-2023-5768](https://insights.sbomify.com/CVE-2023-5768/): Denial of service in RTU500 series (medium 5.9)
- [CVE-2023-5769](https://insights.sbomify.com/CVE-2023-5769/): Cross-site scripting in RTU500 (medium 5.4)
- [CVE-2026-1772](https://insights.sbomify.com/CVE-2026-1772/): Information disclosure in RTU500 series CMU firmware (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-2081 and fix it if it is affected.

What it is: CVE-2022-2081 is a high-severity denial of service vulnerability in Hitachi Energy RTU500 series CMU firmware, published on 4 Jan 2024. 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-2022-2081 in the wild and no public exploit code.

Affected product: Hitachi Energy RTU500 series CMU firmware. 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-2022-2081/ (Markdown: https://insights.sbomify.com/CVE-2022-2081/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-2081
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-2081
- OSV: https://osv.dev/vulnerability/CVE-2022-2081

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-2081/
Summaries are generated and may contain mistakes; the official description above is the record.