From: ./cap-strap-0.1.5/lib/cap-strap/helpers.rb User supplied input isn't properly sanitized for #{user} and #{password} This can lead to command injection if this gem is used in the context of a rails application. Secondly the password is exposed to the process table listing. The password crypt hash is also going to have the same 'sa' salt every time. 022-def create_user(user, password) 23- unless user_exists?(user) 24- command = "useradd -s /bin/bash -d /home/{user}" 25: command << " -p `perl -e print crypt({password}, salt)`" unless password.empty? 26- command << " -m {user}" 27- run "{sudo} #{command}" 28- end