A flaw in Sky UK's court mandated piracy filter can be exploited to block almost any website, copyright news website TorrentFreak has found out.
Courts in the UK have ordered major ISPs to implement filters that block access to websites accused of providing pirated content, including The Pirate bay and TV torrent indexer EZTV.
This particularly serious flaw was in fact discovered by EZTV, after the site's admins change their DNS entry to point the domain name at popular copyright news website TorrentFreak. But what happened next confounded both EZTV's admins and the people who run TorrentFreak, as the news website found itself blocked by Sky's filters.
What may have happened was that once Sky's filters detected that eztv's domain name had pointed to a new IP address, the automated system immediately added that new IP address to its filters, thus blocking TorrentFreak. Using this method, websites that are part of the block can change their DNS settings to that of another website, and have that website blocked as well.
Sky has not yet responded to the potential flaw in their system, which appears to only affect Sky customers at the moment. EZTV has now ended their experiment and have removed TorrentFreak's IP address from their DNS settings, which will hopefully permit access to TorrentFreak once again for Sky customers.