Time Capsule (AirMac ?)の内側からnmapポートスキャンするとポート21, 554, 7070で偽陽性(open)判定になるという話.有名な話なのこれ? 2時間盗られた orz.

it appears that Time Capsule was trying to “help” the situation by proxying certain protocols. The issue is that it doesn’t even check with the server on some of the protocols to see if a connection can actually be obtained, it just makes it appear as though one has been granted and passes along follow-up requests.
……
So, if you’re seeing some unexpected results of ports 21, 554, and 7070 being open on a remote server, I hope you find this blog post so you can quickly check if it’s a piece of Apple networking hardware that’s causing the issue.

Are ports 21, 554, and 7070 open or closed? The answer is yes. – nephtali blog