The following security updates has been released for Ubuntu Linux:

USN-3616-2: Python Crypto vulnerability
USN-3622-1: Wayland vulnerability
USN-3623-1: ubuntu-release-upgrader vulnerability

USN-3616-2: Python Crypto vulnerability

==========================================================================
Ubuntu Security Notice USN-3616-2
April 09, 2018

python-crypto vulnerability
==========================================================================

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

- Ubuntu 12.04 ESM

Summary:

Python Crypto could expose sensitive information.

Software Description:
- python-crypto: cryptographic algorithms and protocols for Python

Details:

USN-3616-1 fixed a vulnerability in Python Crypto. This update provides
the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

 It was discovered that Python Crypto incorrectly generated ElGamal key
 parameters. A remote attacker could possibly use this issue to obtain
 sensitive information.

Update instructions:

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

Ubuntu 12.04 ESM:
  python-crypto 2.4.1-1ubuntu0.3
  python3-crypto 2.4.1-1ubuntu0.3

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

References:
  https://usn.ubuntu.com/usn/usn-3616-2
  https://usn.ubuntu.com/usn/usn-3616-1
  CVE-2018-6594

USN-3622-1: Wayland vulnerability

==========================================================================
Ubuntu Security Notice USN-3622-1
April 09, 2018

wayland vulnerability
==========================================================================

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

- Ubuntu 17.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Wayland could be made to crash or run programs if it opened a specially
crafted file.

Software Description:
- wayland: Wayland compositor infrastructure

Details:

It was discovered that the Wayland Xcursor support incorrectly handled
certain files. An attacker could use these issues to cause Wayland to
crash, resulting in a denial of service, or possibly execute arbitrary
code.

Update instructions:

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

Ubuntu 17.10:
libwayland-cursor0 1.14.0-1ubuntu0.1

Ubuntu 16.04 LTS:
libwayland-bin 1.12.0-1~ubuntu16.04.3
libwayland-client0 1.12.0-1~ubuntu16.04.3
libwayland-cursor0 1.12.0-1~ubuntu16.04.3
libwayland-dev 1.12.0-1~ubuntu16.04.3
libwayland-doc 1.12.0-1~ubuntu16.04.3
libwayland-server0 1.12.0-1~ubuntu16.04.3

Ubuntu 14.04 LTS:
libwayland-cursor0 1.4.0-1ubuntu1.1

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
https://usn.ubuntu.com/usn/usn-3622-1
CVE-2017-16612

Package Information:
https://launchpad.net/ubuntu/+source/wayland/1.14.0-1ubuntu0.1
https://launchpad.net/ubuntu/+source/wayland/1.12.0-1~ubuntu16.04.3
https://launchpad.net/ubuntu/+source/wayland/1.4.0-1ubuntu1.1

USN-3623-1: ubuntu-release-upgrader vulnerability

==========================================================================
Ubuntu Security Notice USN-3623-1
April 09, 2018

ubuntu-release-upgrader vulnerability
==========================================================================

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

- Ubuntu 17.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

ubuntu-release-upgrader incorrectly opened as browser as an administrator.

Software Description:
- ubuntu-release-upgrader: manage release upgrades

Details:

It was discovered that ubuntu-release-upgrader did not correctly drop
permissions before opening a browser to view the release notes. This update
fixes the issue.

Update instructions:

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

Ubuntu 17.10:
python3-distupgrade 1:17.10.11

Ubuntu 16.04 LTS:
python3-distupgrade 1:16.04.25

Ubuntu 14.04 LTS:
python3-distupgrade 1:0.220.10

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

References:
https://usn.ubuntu.com/usn/usn-3623-1
https://launchpad.net/bugs/1174007

Package Information:
https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:17.10.11
https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:16.04.25
https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:0.220.10