Encrypted email service, Tutanota was hit with a series of DDoS attacks this week targeting its website fist and its DNS providers later. The company quickly mitigated the attacks by restricting an overreacting IP-block responsible for the attacks. Some of the company’s 2 million users were not able to access the service for several hours following the DDoS attack. The German company has enhanced anti-DDoS measures to make it quicker to such kinds of attacks in the future.”]
Source: https://securityaffairs.co/wordpress/108502/hacking/tutanota-suffers-ddos-attacks.html