Mastering Linux Security and Hardening - Second Edition

Hands-on lab – installing and using ssh_scan

For this lab, you can use your Ubuntu machine or either of your CentOS machines. Let's get started:

1. ssh_scan isn't in the repositories of any of our Linux distributions. It's written in the Ruby language and comes packaged as a Ruby gem. To get started, we need to install the ruby and gem packages. On Ubuntu, do the following:

sudo apt updatesudo apt install ruby gem

On CentOS 7, do the following:

sudo yum install ruby gem

On CentOS 8, do the following:

sudo dnf install ruby gem

2. Install the ssh_scan gem by using the following command:

sudo gem install ssh_scan

3. In all cases, the ssh_scan executable will be installed in the /usr/local/bin/ directory. A long-standing quirk of CentOS is that if ...