I use Trend Micro for my anti-virus software. Each month I get a report on what it has found. Normally, this is a few hits on my desktop and zero hits on my laptop. However, the September report had 349 web threats on my desktop and 10 on my laptop (used mostly just around breakfast). Most of these web threats were from t.co with a few from democracyk.com and all rated Dangerous.
Any way to find out where these are coming from? Those are not sites I visit.
Your browser visits sites you never see in the URL at the top as it can have to retrieve stuff to fill the page from all over the place to fill the page. Advertisements especially, but also some thing as simple as pictures. And it only takes one view of a questionable site that has nasty stuff linked that way for that to happen.
I use Firefox as my browser. I run the ad blocker Adblock-Plus, as well as the paid versions of Malwarebytes and Bitdefender. Adblock-Plus, avoids showing me a LOT of advertising, though some sites won’t display because the ads (their revenue stream) are blocked. I’ve never bothered to figure out how Malwarebytes and Bitdefender share their AV functions. They done seem to fight each other. As I look at the top line of my browser the Malwarebytes icon has (2), indicating it blocked two sites. On another browser instance that goes up to (2k+), and Adblock-Plus blocked 355 ads. When I wake up my machine after it has been idle, BitDefender does a scan, but I can only recall once that it found anything.
Years ago I ran only free AV tools, or the free versions of paid tools. When I grew more wary I did a bunch of reading and began paying for my protection. The last time I did a review I ended up with those two, and so far so good.
I guess I should have noted that I know about the browser accessing sites other than the URL displayed … but I am wondering if there is a way to tell where these references are coming from.
I run both Chrome and Firefox. Both have AdBlock Plus and Chrome also has uBlock Origin. That’s not really by design, but an accident of history. Only Chrome is actively used on the laptop, but both are used every day on the desktop.
You could try blocking them - both browsers offer that - and wait to see when/if any warnings show up.