Electrum servers are still under a sustained Denial-of-Service (DoS) attack. The wallet developers announced the issue on April 7, 2018.In correspondence with Bitcoin Magazine, Electrum developer Thomas Voegtlin speculated that the attack may be a form of retaliation from a phishing attacker who has been targeting Electrum in recent weeks. Since his phishing attacks had been thwarted, the attacker could now be resorting to DoS attacks instead, simply to frustrate Electrum developers and users. Voegtlin pointed out that, if this is the case, the behavior “is not rational” given the incumbent waste of the attacker’s resources.A DoS attack is a fairly straightforward means of disrupting server activity, usually carried out by flooding a server with frivolous requests from a variety of different sources to overwhelm its processing capacity. Attacks of this nature can be carried out by an individual or by a number of actors, as the key method of attack is simply to overwhelm the server itself.When a DoS attack targets a light wallet such as Electrum, it exploits the fact that users do not need to run their own nodes or connect directly to the Bitcoin network and, instead, connect to Electrum servers. By overwhelming these servers with DoS attacks, the wallets become less usable, as it takes a while to find a working server.It’s also possible that the DoS is being carried out by the same person (or group) that was behind the phish...
