After The Pirate Bay switched to CloudFlare's SSL service it is no longer being blocked by most UK Internet providers. Subscribers of BT, EE, Virgin and TalkTalk can reach the site without problems via the default https address. The "bug" also affects secure versions of other blocked sites, but not all.

Following a series of blocking orders issued by the High Court, several UK ISPs are required to restrict access to many of the world’s largest torrent sites and streaming portals.

The most prominent target of these blocks is without doubt The Pirate Bay. As one of the most visited sites on the Internet it has been a thorn in the side of the entertainment industries for years.

The Pirate Bay was one of the first sites on the UK blocklist and access has been barred since 2012. Or rather should have been barred.

For a few weeks most UK Internet subscribers have been able to access TPB just fine. Ever since the site switched to CloudFlare and made the secure https://thepiratebay.se version default, it has become widely accessible again.

TorrentFreak did a quick round among subscribers of various ISPs and found that The Pirate Bay is no longer blocked by Virgin Media, TalkTalk, BT and EE. At the time of writing only Sky appears to block the site consistently.

As a result, The Pirate Bay’s direct UK traffic is steadily increasing.

The Pirate Bay is not the only site that’s widely accessible again. The same applies to the https versions of Torrentz.eu, Rarbg.com, Isohunt.to and various other ‘blocked’ sites. For some sites, including Kickass.to and Extratorrent, the results vary per ISP.

The operator of the Pirate Bay proxy ilikerainbows.co, which had its own domain name added to the blocklist last week, believes that the unblocking relates to the use of https strict.

“I believe it’s because of how CloudFlare works, Simply put when you enable HTTPS Strict on CloudFlare they remove the HTTP Header from the request during HTTPS Connections, thus when they try to inspect the header to a list of ‘banned’ websites it won’t register,” Rainbows’ operator tells TF.

“So any site that uses CloudFlare, has a properly configured and signed SSL Certificate and enables HTTPS-Strict under CloudFlare should be able to evade the ban that’s imposed by Virgin and perhaps other providers,” he adds.

What further complicates the matter is the fact that it’s harder to block The Pirate Bay by its IP-address, as the true location is hidden by CloudFlare’s network of addresses now.

While it may be harder to block sites, it’s not impossible. Sky appears to have no trouble keeping sites blocked, although that probably requires some rather advanced and invasive monitoring tools.

TF asked several ISPs for a comment on the issue and Virgin Media informed us that they still comply with the court order.

“Virgin Media is required to block certain sites by the UK High Court. As a responsible ISP, we comply with court orders addressed to us,” a spokesperson informed TF this morning.

Virgin’s comment suggests that the https version of TPB is not covered by the order at all, and that it was previously blocked by IP-address. However, Virgin couldn’t comment on this suggestion.

We’ll update this article as more information comes in.