Taika Waititi's box office smash Thor Ragnarok wasn't due to hit streaming services until February 20.

But the film has leaked early - and is being pirated mercilessly on torrent sites.

As Gizmodo reports, the leak reportedly came when pre-orders for the movie were accidentally approved early through on-demand service Vudu.

Within hours, the film had appeared on torrent sites and was topping download stats. One torrent had been downloaded 15,000 times.

Advertisement

quoted one Vudu user from Reddit who'd been given access to the film early.

"I pre-ordered Thor Ragnarok on Vudu yesterday and it links it to my iTunes also. But curiously it showed up in my iTunes library this morning (pre-orders shouldn't). And now I can watch the full movie in HD.

"I obviously downloaded it right away. I know its supposed to come out February 20."

Waititi's comical take on the Marvel super hero was a box office smash upon its release in October, raking in $852 million.

It was also a hit with critics, scoring a 92 per cent approval rating on Rotten Tomatoes.