We're often so focused on who is getting into our infrastructure that we forget about who or what might be getting out. It's a natural tendency, of course, given the focus that InfoSec has traditionally had, and given that we still have the problem of people getting in. There's a quote at the end of this article about the Hannaford breach:
"Clearly, there was a pathway back out of the network that Hannaford should have closed,"
How many organizations implicitly trust outbound connections from their own servers? How many organizations inspect the content and patterns of outbound connections? In this case, Hannaford might have seen correlation between credit cards being processed and a connection out to "an overseas destination," or at least an unexplained outbound connection to that destination on a regular basis.
Having just watched Ocean's 11 last night, I'm reminded that overcoming the challenge of getting into the vault is worthless if you can't manage to get out with the cash.