Imgur, the photo-sharing website, has been exploited in a distributed denial-of-service (DDoS) attack on the popular imageboards 4chan and 8chan.
The DDoS attack, first made public by an Imgur employee on Reddit, used Imgur links to send large amounts of traffic to the imageboards. When a user on Reddit's 4chan subreddit clicked on an Imgur link, the link opened a hidden window and loads tons of image files on the 4chan/8chan servers. This slowed down traffic to the servers and weakened the sites.
Imgur notes it's still important to take precautionary steps and clear your browser's cache, including browser data and cookies.