Dyn announced on Friday morning that it has been the subject of a cyberattack that then caused major problems for numerous websites. People have reported issues with Twitter, Spotify, SoundCloud, Vox Media sites, Airbnb and numerous other sites.
The attack was resolved as of 9:20 a.m. EST, Dyn said.
Writing on its website, Dyn said that starting at about 7:00 a.m. EST, the company "began monitoring and mitigating a DDoS attack against our Dyn Managed DNS infrastructure. Some customers may experience increased DNS query latency and delayed zone propagation during this time. Updates will be posted as information becomes available."
DDoS stands for "distributed denial of service" and is a common tactic used by hackers to take down internet-connected servers. In a DDoS attack, malicious users build a network of computers that then send massive amounts of traffic to particular servers with the goal of denying the use of those servers to other users, according to Cisco.
The attack is mainly affecting the eastern United States, Dyn said.