UPDATE: The issue should be resolved at this time and everything should be back to normal. If you have previously paused CloudFlare please make sure to re-enable it in order to route traffic and get back all the benefits of using it. Please reach out in case you notice any problems.
Several customers are currently affected by a bug that affects communication between Cloudflare and our servers. The issue is being investigated by our Systems team along with CloudFlare and CloudLinux. We will be deploying a fix in the coming hours. In the mean time, a workaround would be to temporarily pause Cloudflare routing for your domain name and load the site directly from the server. We will update here once we have deployed a fix and everything's back to normal.