USN-3530-1: WebKitGTK+ vulnerabilities

11 January 2018

webkit2gtk vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 17.10
  • Ubuntu 17.04
  • Ubuntu 16.04 LTS


WebKitGTK+ could be made to expose sensitive information.

Software Description

  • webkit2gtk - Web content engine library for GTK+


It was discovered that speculative execution performed by modern CPUs could leak information through a timing side-channel attack, and that this could be exploited in web browser JavaScript engines. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit this to obtain sensitive information from other domains, bypassing same-origin restrictions. (CVE-2017-5753, CVE-2017-5715)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 17.10
libjavascriptcoregtk-4.0-18 - 2.18.5-0ubuntu0.17.10.1
libwebkit2gtk-4.0-37 - 2.18.5-0ubuntu0.17.10.1
Ubuntu 17.04
libjavascriptcoregtk-4.0-18 - 2.18.5-0ubuntu0.17.04.1
libwebkit2gtk-4.0-37 - 2.18.5-0ubuntu0.17.04.1
Ubuntu 16.04 LTS
libjavascriptcoregtk-4.0-18 - 2.18.5-0ubuntu0.16.04.1
libwebkit2gtk-4.0-37 - 2.18.5-0ubuntu0.16.04.1

To update your system, please follow these instructions:

This update uses a new upstream release, which includes additional bug fixes. After a standard system update you need to restart any applications that use WebKitGTK+, such as Epiphany, to make all the necessary changes.