Tails is a Linux-based highly secure Operating System, specially designed and optimized to preserve users’ anonymity and privacy. Hacker, who named himself “Sum guy”, managed to access the website as administrator and edited the homepage content with the following message. All other pages on the Tails website are working just fine, but at this moment it is not clear whether the hacker has also modified the OS Image or not. So readers are advised to do not download the OS from the website, at least for a few days.
Source: https://thehackernews.com/2014/06/tails-operating-system-website-has-beed.html