USN-3530-1: WebKitGTK+ vulnerabilities

Ubuntu Security Notice USN-3530-1

11th 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

Summary

WebKitGTK+ could be made to expose sensitive information.

Software description

webkit2gtk
– Web content engine library for GTK+

Details

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 version:

Ubuntu 17.10:: libwebkit2gtk-4.0-37

2.18.5-0ubuntu0.17.10.1; libjavascriptcoregtk-4.0-18

2.18.5-0ubuntu0.17.10.1
Ubuntu 17.04:: libwebkit2gtk-4.0-37

2.18.5-0ubuntu0.17.04.1; libjavascriptcoregtk-4.0-18

2.18.5-0ubuntu0.17.04.1
Ubuntu 16.04 LTS:: libwebkit2gtk-4.0-37

2.18.5-0ubuntu0.16.04.1; libjavascriptcoregtk-4.0-18

2.18.5-0ubuntu0.16.04.1

To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.

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.