The following updates has been released for Ubuntu Linux:

USN-3675-3: GnuPG vulnerability
GnuPG could be made to incorrectly interpret the status of the cryptographic operation if it received specially crafted file. Available for Ubuntu 12.04 ESM

USN-3687-1: WebKitGTK+ vulnerabilities
A large number of security issues were discovered in the WebKitGTK+ Web and JavaScript engines. Available for Ubuntu 16.04 LTS, 17.10, and 18.04 LTS

USN-3675-3: GnuPG vulnerability

==========================================================================
Ubuntu Security Notice USN-3675-3
June 18, 2018

gnupg vulnerability
==========================================================================

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

- Ubuntu 12.04 ESM

Summary:

GnuPG could be made to incorrectly interpret the status of the
cryptographic operation if it received specially crafted file.

Software Description:
- gnupg: GNU privacy guard - a free PGP replacement

Details:

USN-3675-1 fixed a vulnerability in GnuPG. This update provides
the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

 Marcus Brinkmann discovered that during decryption or verification,
 GnuPG did not properly filter out terminal sequences when reporting
 the original filename. An attacker could use this to specially craft a
 file that would cause an application parsing GnuPG output to
 incorrectly interpret the status of the cryptographic operation
 reported by GnuPG. (CVE-2018-12020)

Update instructions:

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

Ubuntu 12.04 ESM:
  gnupg 1.4.11-3ubuntu2.11

In general, a standard system update will make all the necessary
changes.

References:
  https://usn.ubuntu.com/usn/usn-3675-3
  https://usn.ubuntu.com/usn/usn-3675-1
  CVE-2018-12020

USN-3687-1: WebKitGTK+ vulnerabilities

==========================================================================
Ubuntu Security Notice USN-3687-1
June 18, 2018

webkit2gtk vulnerabilities
==========================================================================

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

- Ubuntu 18.04 LTS
- Ubuntu 17.10
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in WebKitGTK+.

Software Description:
- webkit2gtk: Web content engine library for GTK+

Details:

A large number of security issues were discovered in the WebKitGTK+ Web and
JavaScript engines. If a user were tricked into viewing a malicious
website, a remote attacker could exploit a variety of issues related to web
browser security, including cross-site scripting attacks, denial of service
attacks, and arbitrary code execution.

Update instructions:

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

Ubuntu 18.04 LTS:
libjavascriptcoregtk-4.0-18 2.20.3-0ubuntu0.18.04.1
libwebkit2gtk-4.0-37 2.20.3-0ubuntu0.18.04.1

Ubuntu 17.10:
libjavascriptcoregtk-4.0-18 2.20.3-0ubuntu0.17.10.1
libwebkit2gtk-4.0-37 2.20.3-0ubuntu0.17.10.1

Ubuntu 16.04 LTS:
libjavascriptcoregtk-4.0-18 2.20.3-0ubuntu0.16.04.1
libwebkit2gtk-4.0-37 2.20.3-0ubuntu0.16.04.1

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.

References:
https://usn.ubuntu.com/usn/usn-3687-1
CVE-2018-12293, CVE-2018-4190, CVE-2018-4199, CVE-2018-4218,
CVE-2018-4222, CVE-2018-4232, CVE-2018-4233

Package Information:
https://launchpad.net/ubuntu/+source/webkit2gtk/2.20.3-0ubuntu0.18.04.1
https://launchpad.net/ubuntu/+source/webkit2gtk/2.20.3-0ubuntu0.17.10.1
https://launchpad.net/ubuntu/+source/webkit2gtk/2.20.3-0ubuntu0.16.04.1