This was announced on the Network Status page but I thought I would re post it here in case anyone come here first.
Due to a recently reported exploit involving SSH it has become necessary to temporarily block SSH access to our servers. While we understand this is a drastic step, protecting your data and the integrity of our servers is our top priority. We apologize for the inconvenience and can assure you that we are working to resolve this issue and restore SSH access as soon as possible. We will post updates as more info is gathered on this recent exploit. For more information about the exploit please see the following:

Thank you for your patience and understanding while our team works to resolve this issue.
I realized something was up when I went to SFTP into one of my clients cPanel account. Some cPanel account seem to have SSH restored so this may not affect you. It could also affect you if you use something such as MySQL Workbench to log in to manage databases.