# CVE-2021-27196: Specially Crafted IEC 61850 Protocol Sequence Vulnerability

> An attacker on the IEC 61850 network can force Hitachi ABB Power Grids devices to reboot, causing a temporary denial of service.

- **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:** 14 Jun 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-xc3v-wx52-jg7g

## What is CVE-2021-27196?

CVE-2021-27196 is a high-severity denial of service vulnerability in n/a, published on 14 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper Input Validation vulnerability in Hitachi ABB Power Grids Relion 670 Series, Relion 670/650 Series, Relion 670/650/SAM600-IO, Relion 650, REB500, RTU500 Series, FOX615 (TEGO1), MSM, GMS600, PWC600 allows an attacker with access to the IEC 61850 network with knowledge of how to reproduce the attack, as well as the IP addresses of the different IEC 61850 access points (of IEDs/products), to force the device to reboot, which renders the device inoperable for approximately 60 seconds. This vulnerability affects only products with IEC 61850 interfaces. This issue affects: Hitachi ABB Power Grids Relion 670 Series 1.1; 1.2.3 versions prior to 1.2.3.20; 2.0 versions prior to 2.0.0.13; 2.1; 2.2.2 versions prior to 2.2.2.3; 2.2.3 versions prior to 2.2.3.2. Hitachi ABB Power Grids Relion 670/650 Series 2.2.0 versions prior to 2.2.0.13. Hitachi ABB Power Grids Relion 670/650/SAM600-IO 2.2.1 versions prior to 2.2.1.6. Hitachi ABB Power Grids Relion 650 1.1; 1.2; 1.3 versions prior to 1.3.0.7. Hitachi ABB Power Grids REB500 7.3; 7.4; 7.5; 7.6; 8.2; 8.3. Hitachi ABB Power Grids RTU500 Series 7.x version 7.x and prior versions; 8.x version 8.x and prior versions; 9.x version 9.x and prior versions; 10.x version 10.x and prior versions; 11.x version 11.x and prior versions; 12.x version 12.x and prior versions. Hitachi ABB Power Grids FOX615 (TEGO1) R1D02 version R1D02 and prior versions. Hitachi ABB Power Grids MSM 2.1.0 versions prior to 2.1.0. Hitachi ABB Power Grids GMS600 1.3.0 version 1.3.0 and prior versions. Hitachi ABB Power Grids PWC600 1.0 versions prior to 1.0.1.4; 1.1 versions prior to 1.1.0.1.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-27196?

It affects 9 products.


Products: Hitachienergy Fox615 Tego1 Firmware, Hitachienergy Gms600 Firmware, Hitachienergy Modular Switchgear Monitoring Firmware, Hitachienergy Pwc600 Firmware, Hitachienergy Reb500 Firmware, Hitachienergy Relion 650 Firmware, Hitachienergy Relion 670 Firmware, Hitachienergy Relion Sam600-Io Firmware, Hitachienergy Rtu500 Firmware.

## How do I fix CVE-2021-27196?

No fix has been published for CVE-2021-27196 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-27196 being exploited?

There is no known exploitation of CVE-2021-27196 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2022-3353](https://insights.sbomify.com/CVE-2022-3353/): IEC 61850 MMS-Server Vulnerability in multiple Hitachi Energy Products (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-27196 and fix it if it is affected.

What it is: CVE-2021-27196 is a high-severity denial of service vulnerability in n/a, published on 14 Jun 2021. 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-2021-27196 in the wild and no public exploit code.

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-2021-27196/ (Markdown: https://insights.sbomify.com/CVE-2021-27196/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-27196
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-27196
- OSV: https://osv.dev/vulnerability/CVE-2021-27196

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-27196/
Summaries are generated and may contain mistakes; the official description above is the record.