# CVE-2016-9219: Denial of service in Cisco Wireless LAN Controller

> An unauthenticated remote attacker can cause a Cisco Wireless LAN Controller to unexpectedly reload by sending a crafted IPv6 UDP packet.

- **Severity:** High 7.5 (`CVSS:3.0/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:** 6 Apr 2017
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-cf5v-7xgc-j383

## What is CVE-2016-9219?

CVE-2016-9219 is a high-severity denial of service vulnerability in Cisco Wireless Lan Controller Software, published on 6 Apr 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability with IPv6 UDP ingress packet processing in Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause an unexpected reload of the device. The vulnerability is due to incomplete IPv6 UDP header validation. An attacker could exploit this vulnerability by sending a crafted IPv6 UDP packet to a specific port on the targeted device. An exploit could allow the attacker to impact the availability of the device as it could unexpectedly reload. This vulnerability affects Cisco Wireless LAN Controller (WLC) running software version 8.2.121.0 or 8.3.102.0. Cisco Bug IDs: CSCva98592.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2016-9219?

It affects 2 products.


Products: Cisco Wireless Lan Controller Firmware, Cisco Wireless Lan Controller Software.

## How do I fix CVE-2016-9219?

No fix has been published for CVE-2016-9219 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-9219 being exploited?

There is no known exploitation of CVE-2016-9219 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Wireless Lan Controller Software

- [CVE-2017-3854](https://insights.sbomify.com/CVE-2017-3854/): Auth bypass in Cisco Meshed Wireless LAN Controller (high 8.8)
- [CVE-2017-3832](https://insights.sbomify.com/CVE-2017-3832/): Denial of service in Cisco Wireless LAN Controller (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-9219 and fix it if it is affected.

What it is: CVE-2016-9219 is a high-severity denial of service vulnerability in Cisco Wireless Lan Controller Software, published on 6 Apr 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-2016-9219 in the wild and no public exploit code.

Affected product: Cisco Wireless Lan Controller Software. 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-2016-9219/ (Markdown: https://insights.sbomify.com/CVE-2016-9219/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-9219
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-9219
- OSV: https://osv.dev/vulnerability/CVE-2016-9219

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-9219/
Summaries are generated and may contain mistakes; the official description above is the record.