You may have heard about the case of Sierra Corporate Design, Inc. v. David Ritz.
There has been lots of griping and complaining about the fact that doing zone transfers might be illegal. I thought I'd try to give the quick analysis of the case. I'm sure I'm missing a few things here and I'm not a lawyer, but I am a little tired of "hackers" complaining about their rights to do whatever they want being trampled... You can read the judgment here.
In this case David Ritz is being punished for performing unauthorized DNS zone transfers of Sierra Corporate Design's network.
The problem at the federal level is that the CFAA (Computer Fraud and Abuse Act). North Dakota's statute appears to have roughly the same language.
The CFAA has relatively consistently been interpreted so that "Accessing a computer without authorization" hinges on whether the owner of the computer wanted you to perform your action or didn't. The presence or absence of controls to prevent access being generally irrelevant. They have relied on the traditional definition of trespass and attempted to apply it to the electr0nic world.
In the physical world trespass is relatively easy to understand, police, etc. There are obviously corner cases where you can trespass onto unmarked land, not realize you're trespassing, etc. There is a lot of case law for these. At the same time though, if you see a house, you know it isn't your house, and you walk into it, you're trespassing whether or not they locked the door. It is quite clear that you weren't invited and not locking the door doesn't remove the rights of the home owner to prevent trespass.
In the electronic world for example it gets a lot murkier. If I mistype a URL into a tool and attempt to access someone's machine, its pretty clear from both intent and network traffic what was going on. At the same time though, let's say I send a ton of traffic at you, or I start fingerprinting your system. Intent is really the key question here.
Did I knowingly attempt to access your computer without authorization? What was my intent? It is generally the answers to these questions that would be at play in court.
In this specific case a DNS zone transfer isn't the sort of thing you mistakenly do. It isn't isn't the type of data that people generally try to get from other sites as part of browsing the net, etc. In general, and in this case its pretty apparent, you're trying to get data that you wouldn't ordinarily be expecting people to let out. Whether the DNS server was configured to prevent zone transfers isn't really the issue here.
Obviously where this gets tricky is determining whether this is like trespassing onto unmarked land, or walking into someone else's house when they had the door unlocked.
This isn't to say I necessarily agree with the decision, but there is a lot more nuance to this issue than I've seen posted.