# CVE-2014-9717: Auth bypass in n/a

> Local users can bypass mount restrictions to access hidden filesystem locations by exploiting a missing check in the Linux kernel's umount2 system call.

- **Severity:** Medium 6.1 (`CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N`)
- **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:** 2 May 2016
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2014-9717, GHSA-325x-3w5r-2xgh

## What is CVE-2014-9717?

CVE-2014-9717 is a medium-severity authentication bypass vulnerability in Linux kernel, published on 2 May 2016. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

fs/namespace.c in the Linux kernel before 4.0.2 processes MNT_DETACH umount2 system calls without verifying that the MNT_LOCKED flag is unset, which allows local users to bypass intended access restrictions and navigate to filesystem locations beneath a mount by calling umount2 within a user namespace.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2014-9717?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2014-9717?

Apply the vendor's patch.

## Is CVE-2014-9717 being exploited?

There is no known exploitation of CVE-2014-9717 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2014-9717 and fix it if it is affected.

What it is: CVE-2014-9717 is a medium-severity authentication bypass vulnerability in Linux kernel, published on 2 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-2014-9717 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2014-9717/ (Markdown: https://insights.sbomify.com/CVE-2014-9717/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2014-9717
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2014-9717
- OSV: https://osv.dev/vulnerability/CVE-2014-9717

---
From sbomify Insights: https://insights.sbomify.com/CVE-2014-9717/
Summaries are generated and may contain mistakes; the official description above is the record.