Ubuntu Security Notice USN-3795-3

==========================================================================
Ubuntu Security Notice USN-3795-3
November 29, 2018

libssh regression
==========================================================================

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:

USN-3795-1 and USN-3795-2 introduced a regression in libssh.

Software Description:
– libssh: A tiny C SSH library

Details:

USN-3795-1 and USN-3795-2 fixed a vulnerability in libssh. The upstream
fix introduced a regression. This update fixes the problem.

Original advisory details:

Peter Winter-Smith discovered that libssh incorrectly handled
authentication when being used as a server. A remote attacker could use
this issue to bypass authentication without any credentials.

Update instructions:

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

Ubuntu 18.10:
libssh-4 0.8.1-1ubuntu0.3

Ubuntu 18.04 LTS:
libssh-4 0.8.0~20170825.94fa1e38-1ubuntu0.2

Ubuntu 16.04 LTS:
libssh-4 0.6.3-4.3ubuntu0.2

Ubuntu 14.04 LTS:
libssh-4 0.6.1-0ubuntu3.5

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

References:
https://usn.ubuntu.com/usn/usn-3795-3
https://usn.ubuntu.com/usn/usn-3795-1
https://launchpad.net/bugs/1805348

Package Information:
https://launchpad.net/ubuntu/+source/libssh/0.8.1-1ubuntu0.3
https://launchpad.net/ubuntu/+source/libssh/0.8.0~20170825.94fa1e38-1ubuntu0.2
https://launchpad.net/ubuntu/+source/libssh/0.6.3-4.3ubuntu0.2
https://launchpad.net/ubuntu/+source/libssh/0.6.1-0ubuntu3.5