saltstack/salt — pull request #10372 by basepi (2014-02-11 23:26:12+00:00)
Title: Fix insecure recommendations in preseed tutorial, Fix #9997

user_data/cloud-init info lives for the life of an instance and is accessible to any user on the system (including non-root owned services, which would then be able to own the server and possibly other parts of the infrastructure)

This fixes that recommendation and puts additional emphasis on the need to make the key distribution secure.