>> reporter: good morning, dave. well, look, this is the beginning of a massive investigation. you're talking about more than 300,000 cases, more than 150 countries. so, yes, there are a lot of governments around the world who want to know who is at the root of this attack, and the job of figuring that out falls on security firms and researchers. one breakthrough now is that a researcher at google has said that code used in the attack bears similarities to code that has been used by a north korean hacking group called the lazarus group. no comment from google, but two major security firms are saying they have found the same similarities. they say this is still a weak connection. they need stronger connections. and another security firm says that the similarity is not unique enough to point in any definitive way to the operator here, but this is one piece of evidence that certainly researchers and security firms are going to be looking at. what they do in these cases in order to find out who is at the origin of these attacks is to try and look for code that's been used by known groups in the past. that may be what led them to