More than ever, websites are blocking users of the anonymizing Tor network or degrading the services they receive. Data published today by Web security company CloudFlare suggests why that is.
In a company blog post entitled "The Trouble with Tor," CloudFlare CEO Matthew Prince says that 94 percent of the requests the company sees coming across the Tor network are "per se malicious." He explains:
That doesn’t mean they are visiting controversial content, but instead that they are automated requests designed to harm our customers. A large percentage of the comment spam, vulnerability scanning, ad click fraud, content scraping, and login scanning comes via the Tor network. To give you some sense, based on data from Project Honey Pot, 18% of global email spam, or approximately 6.5 trillion unwanted messages per year, begin with an automated bot harvesting email addresses via the Tor network.
A graph in the blog post shows that nearly 70 percent of Tor exit nodes were listed as "comment spammer" nodes at some point over the last year.