# CVE-2025-27020: Improper configuration of SSH service in Infinera MTC-9

> Unauthenticated attackers can execute arbitrary commands and access file system data on Infinera MTC-9 devices due to improper SSH configuration.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:** 8 Dec 2025
- **Updated:** 8 Dec 2025
- **Also known as:** GHSA-3645-f6qv-w99w

## What is CVE-2025-27020?

CVE-2025-27020 is a critical authentication bypass vulnerability in Infinera MTC-9, published on 8 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper configuration of the SSH service in Infinera MTC-9 allows an unauthenticated attacker to execute arbitrary commands and access data on file system

.

This issue affects MTC-9: from R22.1.1.0275 before R23.0.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2025-27020?

It affects 1 product.


Products: Nokia Infinera Mtc-9 Firmware.

## How do I fix CVE-2025-27020?

No fix has been published for CVE-2025-27020 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-27020 being exploited?

There is no known exploitation of CVE-2025-27020 in the wild and no public exploit code.

## Other vulnerabilities in Infinera MTC-9

- [CVE-2025-27019](https://insights.sbomify.com/CVE-2025-27019/): Remote shell service (RSH) in Infinera MTC-9 (critical 9.8)
- [CVE-2025-26487](https://insights.sbomify.com/CVE-2025-26487/): Server Side Request Forgery (SSRF) in the web server of Infinera MTC-9 (high 8.6)
- [CVE-2025-26488](https://insights.sbomify.com/CVE-2025-26488/): Improper input validation in XML Management service in Infinera MTC-9 (high 7.5)
- [CVE-2025-26489](https://insights.sbomify.com/CVE-2025-26489/): Improper input validation in Netconf service in Infinera MTC-9 (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-27020 and fix it if it is affected.

What it is: CVE-2025-27020 is a critical authentication bypass vulnerability in Infinera MTC-9, published on 8 Dec 2025. 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-2025-27020 in the wild and no public exploit code.

Affected product: Infinera MTC-9. 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-2025-27020/ (Markdown: https://insights.sbomify.com/CVE-2025-27020/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-27020
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-27020
- OSV: https://osv.dev/vulnerability/CVE-2025-27020

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-27020/
Summaries are generated and may contain mistakes; the official description above is the record.