I never needed to hack our shiny new £50,000 UNIX Server, it was left completely open.
Full rwx permissions and privileges. Just change directory to another user
I was angry at our 3rd party supplier's incompetence but never said anything
It was too useful knowing the salary of everyone in the company
And the secret plans to geographically relocate to a cheaper part of the country, 150 miles away
Four of us, in the know, went to the Managing Director and complained and the plan was kiboshed.
(most of our customers were in the South East)
We set up a meeting at his house one evening
"How do you know all this?"
"Can't say, sorry"
The loophole was never closed