I got a free preview copy of this from NetGalley.
Cyber Attack is a great summary of where cyber crime is now and where it came from (includes a short history). Its depth is shallow, but every term is explained and every historical reference defined (they did not, for instance, assume the reader knows who Hitler was). In that sense it is clearly for young readers.
But honestly, I know a lot of adults who don't know what's in here, and it's a good summary of the basics, so I would recommend it for adult readers who are curious, too, if they're not offended by having all terms defined. It might have a tendency to make people freak out, but the reality is that we're all vulnerable to attack at a personal level as well as on a national level. The article is a good read at the level of a good magazine story, summarizing the major issues in break-out boxes and telling a straightforward story, even when the material itself is somewhat chaotic.