---
title: "CVE-2016-4439\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-2016-4439?format=md
keywords: index, follow
---

# CVE-2016-4439

Publication date 20 May 2016

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**6.7 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2016-4439?format=md#impact-score)

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## Description

The esp\_reg\_write function in hw/scsi/esp.c in the 53C9X Fast SCSI
Controller (FSC) support in QEMU does not properly check command buffer
length, which allows local guest OS administrators to cause a denial of
service (out-of-bounds write and QEMU process crash) or potentially execute
arbitrary code on the QEMU host via unspecified vectors.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2016-4439?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| qemu | 16.04 LTS xenial | Fixed 1:2.5+dfsg-5ubuntu10.3 |
| 15.10 wily | Ignored end of life |
| 14.04 LTS trusty | Fixed 2.0.0+dfsg-2ubuntu1.26 |
| 12.04 LTS precise | Not in release |
| qemu-kvm | 16.04 LTS xenial | Not in release |
| 15.10 wily | 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)
* [Patch details](https://ubuntu.com/security/CVE-2016-4439?format=md#patch-details)

## Notes

---

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

qemu-kvm in precise doesn't build esp.c on Ubuntu

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| qemu | * Other:   <https://lists.gnu.org/archive/html/qemu-devel/2016-05/msg03273.html> * Upstream:   <http://git.qemu.org/?p=qemu.git;a=commit;h=c98c6c105f66f05aa0b7c1d2a4a3f716450907ef> |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

6.7 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 6.7 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-4439)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-4439)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-4439)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-4439)

### Related Ubuntu Security Notices (USN)

+ [USN-3047-1](https://usn.ubuntu.com/USN-3047-1)
+ QEMU vulnerabilities
+ 4 August 2016

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2016-4439>