Yep, as much as your dedicated team of Moderators are strapped in front of their monitors, just sometimes a spammer can register and occasionally they might try to spam you direct by PM!
If you get such a PM, please use the Report button in the message to let the Mods know and they will come down on the scummer like a ton of bricks! DO NOT reply to the PM, and never click on any link/image in the message, there is a pretty good chance you'll be risking infecting your computer if you do so!
The best description of SPAM out there!
https://www.youtube.com/watch?v=anwy2MPT5RE