Keeping your mouth shut is rule number one when it comes to your Bitcoin wealth, but that doesn't mean you're safe from all threats coming from the internet. Even if you browse through well known sites (news sites, web shops, forums, etc) your system might end up getting infected. People quite often only focus on not clicking links, not opening emails they don't know/expect, not download anything, etc, but they ignore that browsing through websites is enough to get infected. I have experienced this once with a very popular news site, and that while I am extremely paranoid when it comes to my overall PC security. Good thing is that nothing is stored on my system since I use a hardware wallet as cold storage. I just secure erased my hdd and installed a fresh copy of Windows. No damage caused.