# CVE-2017-6655: Denial of service in Cisco NX-OS Software Fibre Channel over Ethernet

> An unauthenticated adjacent attacker can cause a denial of service in Cisco NX-OS devices configured for FCoE by triggering a process reload.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Jun 2017
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-ffjq-497x-2qq5

## What is CVE-2017-6655?

CVE-2017-6655 is a medium-severity denial of service vulnerability in Cisco Nx-Os, published on 13 Jun 2017. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in the Fibre Channel over Ethernet (FCoE) protocol implementation in Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition when an FCoE-related process unexpectedly reloads. This vulnerability affects Cisco NX-OS Software on the following Cisco devices when they are configured for FCoE: Multilayer Director Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches. More Information: CSCvc91729. Known Affected Releases: 8.3(0)CV(0.833). Known Fixed Releases: 8.3(0)ISH(0.62) 8.3(0)CV(0.944) 8.1(1) 8.1(0.8)S0 7.3(2)D1(0.47).

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2017-6655?

It affects 5 products.


Products: Cisco Mds 9000 Nx-Os, Cisco Nx-Os, Cisco Nx-Os for Nexus 5500 Platform Switches, Cisco Nx-Os for Nexus 5600 Platform Switches, Cisco Nx-Os for Nexus 7700 Series Switches.

## How do I fix CVE-2017-6655?

No fix has been published for CVE-2017-6655 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-6655 being exploited?

There is no known exploitation of CVE-2017-6655 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Nx-Os

- [CVE-2015-4323](https://insights.sbomify.com/CVE-2015-4323/): Memory corruption in n/a (medium 6.1)
- [CVE-2015-0775](https://insights.sbomify.com/CVE-2015-0775/): Denial of service in n/a (medium 5.0)
- [CVE-2012-1340](https://insights.sbomify.com/CVE-2012-1340/): Denial of service in n/a (medium 5.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-6655 and fix it if it is affected.

What it is: CVE-2017-6655 is a medium-severity denial of service vulnerability in Cisco Nx-Os, published on 13 Jun 2017. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-6655 in the wild and no public exploit code.

Affected product: Cisco Nx-Os. 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-2017-6655/ (Markdown: https://insights.sbomify.com/CVE-2017-6655/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-6655
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-6655
- OSV: https://osv.dev/vulnerability/CVE-2017-6655

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-6655/
Summaries are generated and may contain mistakes; the official description above is the record.