According to BuzzFeed , popular image blogging site Tumblr  has been attacked by a hacker group called GNAA. The hackers seem to have found their way into the site via a security loophole, and have released a worm that may be able to flood a Tumblr user's feed with racist spam. The infection seems able to attack by visiting a Tumblog.
According to a Mashable writer who was affected  by the worm, deleting the offending posts and quickly changing your login details may be enough to stop the infection. But BuzzFeed advises avoiding visiting Tumblr sites other than your own dashboard page. Tumblr will likely fix the issue in short order, but it will damage the company's traffic right now--a shame, since it's only recently joined  the U.S.'s top 10 most visited sites.
As with all security leaks and exploits like this, it's worth remembering that changing your password and ensuring you don't re-use it elsewhere online are good precautions to take.
[Image: Flickr user jessaax ]