I know as hackers, we feel a duty to show people how serious these things are and that we get impatient and annoyed when ignored. And I also know that it's hard for us to reconcile the idea that when we show the owners rather than tell, it's suddenly considered a crime. But it is.
Let's try an analogy. Door locks on houses are ineffective. Think about it. Your house is covered with windows, which are made of glass. Glass is really easy to break. I mean really easy. If you found out your neighbor didn't have a house alarm, you might talk to them and tell them they should get one. If they didn't get one, would you then break into their house one night and walk into their bedroom to show them how dangerous it is?
OK, who knows, maybe you have a weird relationship with your neighbor. Furthermore, this is an imperfect analogy, because here, Rails and Github are both responsible for other people's property.
But now imagine it's a business across town and that you don't actually know the business owner. If you broke into their business to show them their building's security vulnerabilities, you bet your ass they would press charges and I don't think anyone would blame them. Even if you're doing it with the best intentions, it's still vandalism at best.
All of that being said, this is a very effective way of making your point and getting people to fix the problem. That doesn't make it right. But if you're willing to put yourself in harm's way and essentially become a martyr to get these security vulnerabilities fixed, more power to you.
[1] http://news.ycombinator.com/item?id=3643102
[2] http://www.inc.com/magazine/201203/burt-helm/a-silicon-valle...