Is there any malicious software web traffic detection tool or research?

Hi all,
      At present, there are more and more web traffic caused by malicious
softwares. For example, some malicious plugin may periodly visit some sites
to improve their website's  ranking, or some plugins may periodly collect
the users usage profile. Is there some tool or research available to detect
such activities through web traffic analysis?  Thank you!
Regards,
seacxm 


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