---
title: "CVE-2016-5387\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-2016-5387?format=md
keywords: index, follow
---

# CVE-2016-5387

Publication date 18 July 2016

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**8.1 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2016-5387?format=md#impact-score)

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## Description

The Apache HTTP Server through 2.4.23 follows RFC 3875 section 4.1.18 and
therefore does not protect applications from the presence of untrusted
client data in the HTTP\_PROXY environment variable, which might allow
remote attackers to redirect an application's outbound HTTP traffic to an
arbitrary proxy server via a crafted Proxy header in an HTTP request, aka
an "httpoxy" issue. NOTE: the vendor states "This mitigation has been
assigned the identifier CVE-2016-5387"; in other words, this is not a CVE
ID for a vulnerability.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| apache2 | 16.04 LTS xenial | Fixed 2.4.18-2ubuntu3.1 |
| 15.10 wily | Fixed 2.4.12-2ubuntu2.1 |
| 14.04 LTS trusty | Fixed 2.4.7-1ubuntu4.13 |
| 12.04 LTS precise | Fixed 2.2.22-1ubuntu1.11 |

---

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

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

8.1 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 8.1 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-5387)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-5387)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-5387)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-5387)

### Related Ubuntu Security Notices (USN)

+ [USN-3038-1](https://usn.ubuntu.com/USN-3038-1)
+ Apache HTTP Server vulnerability
+ 18 July 2016

### Other references

* <https://httpoxy.org/>
* <https://www.apache.org/security/asf-httpoxy-response.txt>
* <https://www.cve.org/CVERecord?id=CVE-2016-5387>