In many European countries, for example, national courts have ordered ISPs to block access to sites such as The Pirate Bay and Kickass.to.
However, that’s not the only type of blocking and filtering that’s common nowadays. There are thousands of companies, schools and other organizations that voluntarily use commercial blocking software to restrict access to objectionable or threatening sites.
As with all filters, however, there are false positives. TorrentFreak, for example, is often categorized as a file-sharing site, and blocked to prevent copyright infringement or other associated “threats”.
Apparently this is also happening at Microsoft, where the filter managed by the local information security risk management department blocks TorrentFreak on the internal network. Microsoft employees who try to access our site are welcomed with the following message.
“The requested resource has been blocked as an identified risk to your client and the Microsoft corporate network.”
The notice shows that TorrentFreak is blocked under the “peer-to-peer file sharing” category. A false positive, of course, and one that results in a form of overblocking many perfectly secure and legitimate sites are suffering from.
Unfortunately the issues above are not limited to Microsoft. Every other week we are notified by readers who can’t access TorrentFreak since it’s blocked at their work or school because the site is classified as a source of illegal file-sharing. More often than not we’re collateral damage.
Just a few weeks ago we learned that the UK ISP Sky blocked TorrentFreak for all subscribers who turned on their “porn” filter. After the BBC got involved the block was eventually lifted, but other sites may not be so lucky.
If anything, the above shows that these filtering systems can cause harm to legitimate sites, and the people responsible should be called out for it. TorrentFreak reached out to Microsoft to ask for a comment, but thus far without any luck.