The following updates has been released for Debian GNU/Linux:

USN-3806-1: systemd vulnerability
USN-3807-1: NetworkManager vulnerability
USN-3808-1: Ruby vulnerabilities

USN-3806-1: systemd vulnerability

==========================================================================
Ubuntu Security Notice USN-3806-1
November 05, 2018

systemd vulnerability
==========================================================================

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

- Ubuntu 18.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

systemd-networkd could be made to crash or run programs if it received
specially crafted network traffic.

Software Description:
- systemd: system and service manager

Details:

Felix Wilhelm discovered that the systemd-networkd DHCPv6 client
incorrectly handled certain DHCPv6 messages. In configurations where
systemd-networkd is being used, an attacker on the same network could use
this issue to cause systemd-networkd 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 18.10:
systemd 239-7ubuntu10.1

Ubuntu 18.04 LTS:
systemd 237-3ubuntu10.4

Ubuntu 16.04 LTS:
systemd 229-4ubuntu21.6

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

References:
https://usn.ubuntu.com/usn/usn-3806-1
CVE-2018-15688

Package Information:
https://launchpad.net/ubuntu/+source/systemd/239-7ubuntu10.1
https://launchpad.net/ubuntu/+source/systemd/237-3ubuntu10.4
https://launchpad.net/ubuntu/+source/systemd/229-4ubuntu21.6

USN-3807-1: NetworkManager vulnerability

==========================================================================
Ubuntu Security Notice USN-3807-1
November 05, 2018

network-manager vulnerability
==========================================================================

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

- Ubuntu 18.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

NetworkManager could be made to crash or run programs if it received
specially crafted network traffic.

Software Description:
- network-manager: Network connection manager

Details:

Felix Wilhelm discovered that the NetworkManager internal DHCPv6 client
incorrectly handled certain DHCPv6 messages. In non-default configurations
where the internal DHCP client is enabled, an attacker on the same network
could use this issue to cause NetworkManager 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 18.10:
network-manager 1.12.4-1ubuntu1.1

Ubuntu 18.04 LTS:
network-manager 1.10.6-2ubuntu1.1

Ubuntu 16.04 LTS:
network-manager 1.2.6-0ubuntu0.16.04.3

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

References:
https://usn.ubuntu.com/usn/usn-3807-1
CVE-2018-15688

Package Information:
https://launchpad.net/ubuntu/+source/network-manager/1.12.4-1ubuntu1.1
https://launchpad.net/ubuntu/+source/network-manager/1.10.6-2ubuntu1.1
https://launchpad.net/ubuntu/+source/network-manager/1.2.6-0ubuntu0.16.04.3

USN-3808-1: Ruby vulnerabilities

==========================================================================
Ubuntu Security Notice USN-3808-1
November 05, 2018

ruby1.9.1, ruby2.0, ruby2.3, ruby2.5 vulnerabilities
==========================================================================

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

- Ubuntu 18.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in Ruby.

Software Description:
- ruby2.5: Interpreter of object-oriented scripting language Ruby
- ruby2.3: Object-oriented scripting language
- ruby1.9.1: Object-oriented scripting language
- ruby2.0: Object-oriented scripting language

Details:

It was discovered that Ruby incorrectly handled certain X.509
certificates. An attacker could possibly use this issue to
bypass the certificate check. (CVE-2018-16395)

It was discovered that Ruby incorrectly handled certain
inputs. An attacker could possibly use this issue to execute
arbitrary code. (CVE-2018-16396)

Update instructions:

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

Ubuntu 18.10:
libruby2.5 2.5.1-5ubuntu4.1
ruby2.5 2.5.1-5ubuntu4.1

Ubuntu 18.04 LTS:
libruby2.5 2.5.1-1ubuntu1.1
ruby2.5 2.5.1-1ubuntu1.1

Ubuntu 16.04 LTS:
libruby2.3 2.3.1-2~16.04.11
ruby2.3 2.3.1-2~16.04.11

Ubuntu 14.04 LTS:
libruby1.9.1 1.9.3.484-2ubuntu1.13
libruby2.0 2.0.0.484-1ubuntu2.11
ruby1.9.1 1.9.3.484-2ubuntu1.13
ruby1.9.3 1.9.3.484-2ubuntu1.13
ruby2.0 2.0.0.484-1ubuntu2.11

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

References:
https://usn.ubuntu.com/usn/usn-3808-1
CVE-2018-16395, CVE-2018-16396

Package Information:
https://launchpad.net/ubuntu/+source/ruby2.5/2.5.1-5ubuntu4.1
https://launchpad.net/ubuntu/+source/ruby2.5/2.5.1-1ubuntu1.1
https://launchpad.net/ubuntu/+source/ruby2.3/2.3.1-2~16.04.11
https://launchpad.net/ubuntu/+source/ruby1.9.1/1.9.3.484-2ubuntu1.13
https://launchpad.net/ubuntu/+source/ruby2.0/2.0.0.484-1ubuntu2.11