==========================================================================
Ubuntu Security Notice USN-3945-1
April 11, 2019

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 RubyGems.
An attacker could possibly use this issue to execute arbitrary
commands. (CVE-2019-8320)

It was discovered that Ruby incorrectly handled certain inputs.
An attacker could possibly use this issue to execute arbitrary code.
(CVE-2019-8321, CVE-2019-8322, CVE-2019-8323, CVE-2019-8324, CVE-2019-8325)

Update instructions:

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

Ubuntu 18.10:
  libruby2.5                      2.5.1-5ubuntu4.3
  ruby2.5                         2.5.1-5ubuntu4.3

Ubuntu 18.04 LTS:
  libruby2.5                      2.5.1-1ubuntu1.2
  ruby2.5                         2.5.1-1ubuntu1.2

Ubuntu 16.04 LTS:
  libruby2.3                      2.3.1-2~16.04.12
  ruby2.3                         2.3.1-2~16.04.12

Ubuntu 14.04 LTS:
  libruby1.9.1                    1.9.3.484-2ubuntu1.14
  libruby2.0                      2.0.0.484-1ubuntu2.13
  ruby1.9.1                       1.9.3.484-2ubuntu1.14
  ruby1.9.3                       1.9.3.484-2ubuntu1.14
  ruby2.0                         2.0.0.484-1ubuntu2.13

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

References:
  https://usn.ubuntu.com/usn/usn-3945-1
  CVE-2019-8320, CVE-2019-8321, CVE-2019-8322, CVE-2019-8323,
  CVE-2019-8324, CVE-2019-8325

Package Information:
  https://launchpad.net/ubuntu/+source/ruby2.5/2.5.1-5ubuntu4.3
  https://launchpad.net/ubuntu/+source/ruby2.5/2.5.1-1ubuntu1.2
  https://launchpad.net/ubuntu/+source/ruby2.3/2.3.1-2~16.04.12
  https://launchpad.net/ubuntu/+source/ruby1.9.1/1.9.3.484-2ubuntu1.14
  https://launchpad.net/ubuntu/+source/ruby2.0/2.0.0.484-1ubuntu2.13