# CVE-2016-2198: Null dereference in n/a

> A privileged guest user can crash the QEMU process via a null pointer dereference in USB EHCI emulation, causing denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 29 Dec 2016
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2016-2198, GHSA-4fg5-fcph-rgxc, UBUNTU-CVE-2016-2198

## What is CVE-2016-2198?

CVE-2016-2198 is a medium-severity vulnerability in Debian Debian Linux, published on 29 Dec 2016. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

QEMU (aka Quick Emulator) built with the USB EHCI emulation support is vulnerable to a null pointer dereference flaw. It could occur when an application attempts to write to EHCI capabilities registers. A privileged user inside quest could use this flaw to crash the QEMU process instance resulting in DoS.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2016-2198?

It affects 2 products.


Products: Debian Debian Linux, Qemu Qemu.

## How do I fix CVE-2016-2198?

Apply the vendor's patch.

## Is CVE-2016-2198 being exploited?

There is no known exploitation of CVE-2016-2198 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-2198 and fix it if it is affected.

What it is: CVE-2016-2198 is a medium-severity vulnerability in Debian Debian Linux, published on 29 Dec 2016. 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-2016-2198 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2016-2198/ (Markdown: https://insights.sbomify.com/CVE-2016-2198/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-2198
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-2198
- OSV: https://osv.dev/vulnerability/CVE-2016-2198

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-2198/
Summaries are generated and may contain mistakes; the official description above is the record.