"A recent attempt to attack your computer was blocked"

I have been getting a lot of "A recent attempt to attack your computer was blocked" notifications lately, even for web sites that I assume are fairly inocuious, for example, triggered from a google search.

 

In one recent example, the Norton details were "Risk Name: HTTP Tidserv Request...Attacker URL: 7gafd33ja90a.com/NKc0e......"

 

I'd like to avoid using web sites that are risky, but is it really risk to do google searches?

Thanks for any advice!