# CVE-2026-20080: Cisco IEC6400 Edge Compute Appliance SSH Denial of Service Vulnerability

> Unauthenticated remote attackers can cause the SSH service to stop responding via a flood attack, requiring administrators to patch the Cisco IEC6400 appliance.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Jan 2026
- **Updated:** 21 Jan 2026
- **Also known as:** GHSA-4rv8-3xqf-8gfm

## What is CVE-2026-20080?

CVE-2026-20080 is a medium-severity denial of service vulnerability in Cisco Ultra-Reliable Wireless Backhaul, published on 21 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the SSH service of Cisco IEC6400 Wireless Backhaul Edge Compute Software could allow an unauthenticated, remote attacker to cause the SSH service to stop responding.

This vulnerability exists because the SSH service lacks effective flood protection. An attacker could exploit this vulnerability by initiating a denial of service (DoS) attack against the SSH port. A successful exploit could allow the attacker to cause the SSH service to be unresponsive during the period of the DoS attack. All other operations remain stable during the attack.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-20080?


## How do I fix CVE-2026-20080?

No fix has been published for CVE-2026-20080 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-20080 being exploited?

There is no known exploitation of CVE-2026-20080 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-20080 and fix it if it is affected.

What it is: CVE-2026-20080 is a medium-severity denial of service vulnerability in Cisco Ultra-Reliable Wireless Backhaul, published on 21 Jan 2026. 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-2026-20080 in the wild and no public exploit code.

Affected product: Cisco Ultra-Reliable Wireless Backhaul. 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-2026-20080/ (Markdown: https://insights.sbomify.com/CVE-2026-20080/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-20080
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-20080
- OSV: https://osv.dev/vulnerability/CVE-2026-20080

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-20080/
Summaries are generated and may contain mistakes; the official description above is the record.