In addition to the Telcos, multiple other services have experienced problems through the day. These include US Bank, Instagram, Chase, Call of Duty, Snapchat, XBOX Live, Facebook, Fortnite, Playstation Network, Grand Theft Auto, YouTube, Twitter, Hulu, Netflix, Twitch, USPS, Discord, EA, Reddit, Facebook Messenger, Amazon and TikTok. There are many others.
According to data provided by Down Detector there appears to have been a coordinated attack on the major US communication very close to 2pm US Eastern Time, Monday.
The graphs indicate that some companies appeared to have instigated mitigation strategies relatively quickly others (not shown in this image) were even quicker.
Other sites, such as Google, Twitch and YouTube also suffered at the same time. Many of the other sites listed earlier suffered at a later time in the day.
Instead, this has the appearances of a BGP attack. Border Gateway Protocol (BGP) manages the connections between independently operated networks to inform them of reachability. Updates are regularly exchanged, however there is little security on these updates, and they can easily be faked. This seems the more likely attack channel.
Updates will be provided as they become available.