# CVE-2017-5544: Denial of service in n/a

> An attacker can cause a denial of service on FiberHome switches by exhausting SSH connection slots through rapid login attempts, requiring a device restart.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/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:** 23 Jan 2017
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-crmv-fcq6-r57v

## What is CVE-2017-5544?

CVE-2017-5544 is a medium-severity denial of service vulnerability in n/a, published on 23 Jan 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered on FiberHome Fengine S5800 switches V210R240. An unauthorized attacker can access the device's SSH service, using a password cracking tool to establish SSH connections quickly. This will trigger an increase in the SSH login timeout (each of the login attempts will occupy a connection slot for a longer time). Once this occurs, legitimate login attempts via SSH/telnet will be refused, resulting in a denial of service; you must restart the device.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2017-5544?

It affects 1 product.


Products: Fiberhome Fengine S5800 Firmware.

## How do I fix CVE-2017-5544?

No fix has been published for CVE-2017-5544 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-5544 being exploited?

There is no known exploitation of CVE-2017-5544 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-5544 and fix it if it is affected.

What it is: CVE-2017-5544 is a medium-severity denial of service vulnerability in n/a, published on 23 Jan 2017. 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-2017-5544 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-2017-5544/ (Markdown: https://insights.sbomify.com/CVE-2017-5544/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-5544
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-5544
- OSV: https://osv.dev/vulnerability/CVE-2017-5544

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From sbomify Insights: https://insights.sbomify.com/CVE-2017-5544/
Summaries are generated and may contain mistakes; the official description above is the record.