Instagram users are reporting that they've been attacked by a mysterious hack that posts photos of smoothies to their accounts. (We e-mailed Instagram to see if they've got anything to say.)
From the looks of the tweets above and below, it seems the exploit is a phishing scheme, so don't click any weird links on Instagram photos. You probably shouldn't be doing that anyway.
Instagram responded with the following:
Last night a small portion of our users experienced a spam incident where unwanted photos were posted from their accounts. Our security and spam team quickly took actions to secure the accounts involved, and the posted photos are being deleted.