# CVE-2016-6407: Denial of service in n/a

> Remote attackers can cause denial of service on Cisco Web Security Appliances by sending simultaneous HTTP requests with overlapping byte ranges.

- **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:** 17 Sep 2016
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-83cp-8php-jfpv

## What is CVE-2016-6407?

CVE-2016-6407 is a high-severity denial of service vulnerability in Cisco Web Security Appliance, published on 17 Sep 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Cisco AsyncOS through 9.5.0-444 on Web Security Appliance (WSA) devices allows remote attackers to cause a denial of service (link saturation) by making many HTTP requests for overlapping byte ranges simultaneously, aka Bug ID CSCuz27219.

Weakness: CWE-399

## Which versions are affected by CVE-2016-6407?

It affects 1 product.


Products: Cisco Web Security Appliance.

## How do I fix CVE-2016-6407?

No fix has been published for CVE-2016-6407 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-6407 being exploited?

There is no known exploitation of CVE-2016-6407 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Web Security Appliance

- [CVE-2015-6298](https://insights.sbomify.com/CVE-2015-6298/): Command injection in n/a (critical 9.0)
- [CVE-2019-1817](https://insights.sbomify.com/CVE-2019-1817/): Cisco Web Security Appliance Malformed Request Denial of Service Vulnerability (high 8.6)
- [CVE-2018-0410](https://insights.sbomify.com/CVE-2018-0410/): Denial of service in AsyncOS Software for Cisco Web Security Appliances (high 8.6)
- [CVE-2015-6292](https://insights.sbomify.com/CVE-2015-6292/): Denial of service in n/a (high 7.8)
- [CVE-2015-6293](https://insights.sbomify.com/CVE-2015-6293/): Denial of service in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-6407 and fix it if it is affected.

What it is: CVE-2016-6407 is a high-severity denial of service vulnerability in Cisco Web Security Appliance, published on 17 Sep 2016. 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-2016-6407 in the wild and no public exploit code.

Affected product: Cisco Web Security Appliance. 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-2016-6407/ (Markdown: https://insights.sbomify.com/CVE-2016-6407/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-6407
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-6407
- OSV: https://osv.dev/vulnerability/CVE-2016-6407

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-6407/
Summaries are generated and may contain mistakes; the official description above is the record.