Many times a week I see this question that Google has the page title and page description wrong. If you are a law site and the title and description is not about law but about sex or viagra then yeah you have been hacked.
First thing I go do is to check my Google Webmaster Tools but most people have Google Analytics but are lacking Google Webmaster Tools. (tangent) I do not understand why when a user signs up for Google Analytics they are not just signed up for Webmaster Tools. Oh well I took Matt Cutts to task and a few others on this at the Google TC summit in Oct 2013 about this. Hopefully they will do something about this sometime this decade. Till then I get to help out a hacked site at least once a week.
So I will go over hacked sites for users that are on the WordPress CMS. Check your wp-config file, check your .htaccess files, make sure you are running the current version of wordpress, themes, and all plugins. Most hacks come because people do not update and then I say you have nobody to look at other then yourself. Yeah you got issues and you are the person to look at.
After looking everything over and getting the flaws corrected now you have to wait. This can take anywhere from a few days to a few weeks. Again you cannot be angry at anyone but yourself for not paying attention to your site. If you want to speed it up. Submit a new sitemap, fetch as Googlebot, and promote the hell out of the page to get Googlebot to come back and to re-index the site. Yes you have to wait on Google, you dropped the ball you have to wait for it to come back and resolve the updated and more secure site.