# CVE-2017-15129: Use after free in Linux kernel v4.0-rc1 through v4.15-rc5

> An unprivileged local user can trigger a use-after-free in network namespaces, causing kernel crashes and potentially enabling privilege escalation.

- **Severity:** Medium 4.7 (`CVSS:3.1/AV:L/AC:H/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:** 9 Jan 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2017-15129, GHSA-9324-w9gg-mxf6, UBUNTU-CVE-2017-15129

## What is CVE-2017-15129?

CVE-2017-15129 is a medium-severity use after free vulnerability in Canonical Ubuntu Linux, published on 9 Jan 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A use-after-free vulnerability was found in network namespaces code affecting the Linux kernel before 4.14.11. The function get_net_ns_by_id() in net/core/net_namespace.c does not check for the net::count value after it has found a peer network in netns_ids idr, which could lead to double free and memory corruption. This vulnerability could allow an unprivileged local user to induce kernel memory corruption on the system, leading to a crash. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although it is thought to be unlikely.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2017-15129?

It affects 20 products.


Products: Canonical Ubuntu Linux, Fedoraproject Fedora, Linux kernel, Redhat Enterprise Linux, Redhat Enterprise Linux Compute Node Eus, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Eus, Redhat Enterprise Linux for Ibm Z Systems, Redhat Enterprise Linux for Ibm Z Systems Eus, Redhat Enterprise Linux for Power Big Endian, Redhat Enterprise Linux for Power Big Endian Eus, Redhat Enterprise Linux for Power Little Endian Eus, Redhat Enterprise Linux for Real Time, Redhat Enterprise Linux for Real Time for Nfv, Redhat Enterprise Linux for Scientific Computing, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Tus, Redhat Enterprise Linux Server Update Services for Sap Solutions, Redhat Enterprise Linux Workstation.

## How do I fix CVE-2017-15129?

Upgrade to a fixed version.

## Is CVE-2017-15129 being exploited?

There is no known exploitation of CVE-2017-15129 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-2017-15129 and fix it if it is affected.

What it is: CVE-2017-15129 is a medium-severity use after free vulnerability in Canonical Ubuntu Linux, published on 9 Jan 2018. 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-2017-15129 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-2017-15129/ (Markdown: https://insights.sbomify.com/CVE-2017-15129/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-15129
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-15129
- OSV: https://osv.dev/vulnerability/CVE-2017-15129

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-15129/
Summaries are generated and may contain mistakes; the official description above is the record.