# CVE-2016-4805: Use after free in n/a

> Local attackers can trigger a use-after-free in the Linux kernel PPP driver by removing a network namespace, causing system crashes or potential code execution.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 23 May 2016
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2016-4805, GHSA-jwg9-q35h-9vwx, UBUNTU-CVE-2016-4805

## What is CVE-2016-4805?

CVE-2016-4805 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 23 May 2016. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Use-after-free vulnerability in drivers/net/ppp/ppp_generic.c in the Linux kernel before 4.5.2 allows local users to cause a denial of service (memory corruption and system crash, or spinlock) or possibly have unspecified other impact by removing a network namespace, related to the ppp_register_net_channel and ppp_unregister_channel functions.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2016-4805?

It affects 12 products.


Products: Canonical Ubuntu Linux, Linux kernel, Novell Opensuse Leap, Novell Suse Linux Enterprise Desktop, Novell Suse Linux Enterprise Live Patching, Novell Suse Linux Enterprise Module for Public Cloud, Novell Suse Linux Enterprise Real Time Extension, Novell Suse Linux Enterprise Server, Novell Suse Linux Enterprise Software Development Kit, Novell Suse Linux Enterprise Workstation Extension, Oracle Linux, Redhat Enterprise Linux.

## How do I fix CVE-2016-4805?

Apply the vendor's patch.

## Is CVE-2016-4805 being exploited?

There is no known exploitation of CVE-2016-4805 in the wild and no public exploit code.

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-4805 and fix it if it is affected.

What it is: CVE-2016-4805 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 23 May 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-2016-4805 in the wild and no public exploit code.

Affected product: Canonical Ubuntu 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-2016-4805/ (Markdown: https://insights.sbomify.com/CVE-2016-4805/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-4805
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-4805
- OSV: https://osv.dev/vulnerability/CVE-2016-4805

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-4805/
Summaries are generated and may contain mistakes; the official description above is the record.