---
title: "CVE-2016-9643\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-2016-9643?format=md
keywords: index, follow
---

# CVE-2016-9643

Publication date 7 March 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-2016-9643?format=md#impact-score)

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## Description

The regex code in Webkit 2.4.11 allows remote attackers to cause a denial
of service (memory consumption) as demonstrated in a large number of ($
(open parenthesis and dollar) followed by {-2,16} and a large number of +)
(plus close parenthesis).

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| qtwebkit | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.10 kinetic | Not in release |
| 22.04 LTS jammy | Not in release |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.10 groovy | Not in release |
| 20.04 LTS focal | Not in release |
| 19.10 eoan | Ignored end of life |
| 19.04 disco | Not in release |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| qtwebkit-opensource-src | 24.04 LTS noble | Ignored |
| 23.10 mantic | Ignored |
| 23.04 lunar | Ignored end of life, was needs-triage |
| 22.10 kinetic | Ignored end of life, was needs-triage |
| 22.04 LTS jammy | Ignored |
| 21.10 impish | Ignored end of life |
| 21.04 hirsute | Ignored end of life |
| 20.10 groovy | Ignored end of life |
| 20.04 LTS focal | Ignored |
| 19.10 eoan | Ignored end of life |
| 19.04 disco | Ignored end of life |
| 18.10 cosmic | Ignored end of life |
| 18.04 LTS bionic | Ignored end of standard support, was needs-triage |
| 17.10 artful | Ignored end of life |
| 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Ignored end of standard support, was needs-triage |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| qtwebkit-source | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.10 kinetic | Not in release |
| 22.04 LTS jammy | Not in release |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.10 groovy | Not in release |
| 20.04 LTS focal | Not in release |
| 19.10 eoan | Not in release |
| 19.04 disco | Ignored end of life |
| 18.10 cosmic | Ignored end of life |
| 18.04 LTS bionic | Ignored end of standard support, was needs-triage |
| 17.10 artful | Ignored end of life |
| 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Ignored end of standard support, was needs-triage |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| webkit2gtk | 24.04 LTS noble | Not affected |
| 23.10 mantic | Not affected |
| 23.04 lunar | Not affected |
| 22.10 kinetic | Not affected |
| 22.04 LTS jammy | Not affected |
| 21.10 impish | Not affected |
| 21.04 hirsute | Not affected |
| 20.10 groovy | Not affected |
| 20.04 LTS focal | Not affected |
| 19.10 eoan | Not affected |
| 19.04 disco | Not affected |
| 18.10 cosmic | Not affected |
| 18.04 LTS bionic | Not affected |
| 17.10 artful | Not affected |
| 17.04 zesty | Not affected |
| 16.10 yakkety | Fixed 2.16.1-0ubuntu0.16.10.1 |
| 16.04 LTS xenial | Fixed 2.16.1-0ubuntu0.16.04.1 |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| webkitgtk | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.10 kinetic | Not in release |
| 22.04 LTS jammy | Not in release |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.10 groovy | Not in release |
| 20.04 LTS focal | Not in release |
| 19.10 eoan | Not in release |
| 19.04 disco | Not in release |
| 18.10 cosmic | Ignored end of life |
| 18.04 LTS bionic | Ignored end of standard support |
| 17.10 artful | Ignored end of life |
| 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Ignored end of standard support |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |

---

* [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**

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:3.0/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-2016-9643)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-9643)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-9643)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-9643)

### Related Ubuntu Security Notices (USN)

+ [USN-3257-1](https://usn.ubuntu.com/USN-3257-1)
+ WebKitGTK+ vulnerabilities
+ 10 April 2017

### Other references

* <http://www.openwall.com/lists/oss-security/2016/11/26/5>
* <https://www.webkitgtk.org/security/WSA-2017-0003.html>
* <https://www.cve.org/CVERecord?id=CVE-2016-9643>
