---
title: "CVE-2017-7668\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-2017-7668?format=md
keywords: index, follow
---

# CVE-2017-7668

Publication date 19 June 2017

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2017-7668?format=md#impact-score)

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## Description

The HTTP strict parsing changes added in Apache httpd 2.2.32 and 2.4.24
introduced a bug in token list parsing, which allows ap\_find\_token() to
search past the end of its input string. By maliciously crafting a sequence
of request headers, an attacker may be able to cause a segmentation fault,
or to force ap\_find\_token() to return an incorrect value.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| apache2 | 17.04 zesty | Fixed 2.4.25-3ubuntu2.1 |
| 16.10 yakkety | Fixed 2.4.18-2ubuntu4.2 |
| 16.04 LTS xenial | Fixed 2.4.18-2ubuntu3.3 |
| 14.04 LTS trusty | Fixed 2.4.7-1ubuntu4.16 |

---

* [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-2017-7668?format=md#patch-details)

### 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 |
| --- | --- |
| apache2 | * Upstream:   <https://www.apache.org/dist/httpd/patches/apply_to_2.2.32/CVE-2017-7668.patch> * Upstream:   [a585e36](https://github.com/apache/httpd/commit/a585e36e06a53170be6d2d462ceb5b30b8382988) * Upstream:   [ad581ce](https://github.com/apache/httpd/commit/ad581ced12363ce82ffcb16133f236b2e31563e1) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-7668)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2017-7668)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2017-7668)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2017-7668)

### Related Ubuntu Security Notices (USN)

+ [USN-3340-1](https://usn.ubuntu.com/USN-3340-1)
+ Apache HTTP Server vulnerabilities
+ 26 June 2017

+ [USN-3373-1](https://usn.ubuntu.com/USN-3373-1)
+ Apache HTTP Server vulnerabilities
+ 31 July 2017

### Other references

* <https://lists.apache.org/thread.html/55a068b6a5eec0b3198ae7d96a7cb412352d0ffa7716612c5af3745b@%3Cdev.httpd.apache.org%3E>
* <https://www.cve.org/CVERecord?id=CVE-2017-7668>