UPDATE: According to a tweet by Mashable reporter Alex Fitzpatrick, Tumblr is operational again.

In an interview with Gawker, the group responsible for the hack says they warned Tumblr about the exploit weeks ahead of time.

PREVIOUSLY: Tumblr has been hacked.

Check out the Daily Dot's Tumblr page to see what's going on, but be careful – if you visit a hacked page while logged in to Tumblr, your account will be compromised as well.

The worm takes over a Tumblr blog and turns every post into an angsty anti-Tumblr message, railing against

Buzzfeed offers the following as to how the hack was made possible: "One developer suggests that the exploit uses a 'data-uri script tag' in the video embed field. In other words, it runs some sort of script through the section of the site that's supposed to only allow video embed codes from sites like YouTube and Vimeo. A pretty serious security hole!"