---
title: "CVE-2017-7471\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2017-7471?format=md
keywords: index, follow
---

# CVE-2017-7471

Publication date 9 July 2018

Last updated 25 August 2025

---

Ubuntu priority

**High**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**9.0 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2017-7471?format=md#impact-score)

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## Description

Quick Emulator (Qemu) built with the VirtFS, host directory sharing via
Plan 9 File System (9pfs) support, is vulnerable to an improper access
control issue. It could occur while accessing files on a shared host
directory. A privileged user inside guest could use this flaw to access
host file system beyond the shared folder and potentially escalating their
privileges on a host.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2017-7471?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| qemu | 17.04 zesty | Not affected |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |
| 12.04 LTS precise | Not in release |
| qemu-kvm | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not affected |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Notes

---

### [ratliff](https://launchpad.net/~ratliff)

the conversion to at\*() syscalls is not in yakkety/zesty

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.0 · Critical

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Adjacent |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Changed |
  | Confidentiality impact | High |
  | Integrity impact | High |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.0 · Critical |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-7471)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2017-7471)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2017-7471)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2017-7471)

### Other references

* <https://bugzilla.redhat.com/show_bug.cgi?id=1443401>
* <https://www.cve.org/CVERecord?id=CVE-2017-7471>