The following updates has been released for Ubuntu Linux:

USN-3945-1: Ruby vulnerabilities
USN-3946-1: rssh vulnerabilities

USN-3945-1: Ruby vulnerabilities

==========================================================================
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

USN-3946-1: rssh vulnerabilities

==========================================================================
Ubuntu Security Notice USN-3946-1
April 11, 2019

rssh 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:

rssh could be made to run arbitrary commands if it received specially crafted
input.

Software Description:
- rssh: Restricted shell allowing scp, sftp, cvs, svn, rsync or rdist

Details:

It was discovered that rssh incorrectly handled certain command-line arguments
and environment variables. An authenticated user could bypass rssh's command
restrictions, allowing an attacker to run arbitrary commands.

Update instructions:

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

Ubuntu 18.10:
rssh 2.3.4-8ubuntu0.2

Ubuntu 18.04 LTS:
rssh 2.3.4-7ubuntu0.1

Ubuntu 16.04 LTS:
rssh 2.3.4-4+deb8u2ubuntu0.16.04.2

Ubuntu 14.04 LTS:
rssh 2.3.4-4+deb8u2ubuntu0.14.04.2

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

References:
https://usn.ubuntu.com/usn/usn-3946-1
CVE-2019-1000018, CVE-2019-3463, CVE-2019-3464

Package Information:
https://launchpad.net/ubuntu/+source/rssh/2.3.4-8ubuntu0.2
https://launchpad.net/ubuntu/+source/rssh/2.3.4-7ubuntu0.1
https://launchpad.net/ubuntu/+source/rssh/2.3.4-4+deb8u2ubuntu0.16.04.2
https://launchpad.net/ubuntu/+source/rssh/2.3.4-4+deb8u2ubuntu0.14.04.2