Do you see huge traffic from your website coming from referrals? Is the direct traffic more than Google traffic. If yes you are indeed targeted randomly by spammers. What you need is a good setup for filters through your GA account.
I have been battling the spam bots for more than 2 months. They always have new domain after i filtered them. The good thing is that they have reduce as a sign of success. So i am sharing with how you can filter well your unwanted website visitors.
1. Go to you admin account and choose view menu right on the top of your dashboard.
2. Click the filter from known bots and save.
3. Set up specific urls that you want to filter
4. Go to admin again
6. Add new filter
7. Under Create new filter
8. Spam bot1
10. On Select field menu choose Campaign source
11. Paste this pattern
12. Click verify filter and save
Do the same procedure for spam bot2