News that Czech authorities arrested a Russian national on charges related to hacking US targets was widely but incorrectly seen as marking the opening shot in the much-anticipated American response to Russia's recent cyber offensive. In fact the crimes alleged in the arrest have to do with 2012's LinkedIn hack. Credentials stolen in that incident could have been used in subsequent compromises, but that remains a matter of speculation. In any case, the gentleman now facing extradition proceedings in a Prague court isn't exactly Fancy Bear.
Observers think some set of stiff sanctions the likeliest form of US response to Russian election hacking. That hacking is thought unlikely in the extreme to directly control results of voting in November—the voting system is too disparate to make this likely—but analysts see two potential problem areas: disruptive "chaos" on Election Day itself (possibly produced by affecting the AP's poll-tracking and result projection service) and a general erosion of citizens' confidence in the US political system.
Ransomware and IoT botnet-driven DDoS remain the most widespread forms of cybercrime globally. (BankInfo Security's scorecard shows more than 200 ransomware strains now in circulation.) Standards bodies and regulators are working to evolve modes of defense and design, with US financial regulators in particular are promising new guidelines. The proliferation of Mirai source code continues to drive formation of Internet-of-things botnets. KrebsOnSecurity is tracking some firms it believes occupy some demi-monde between legitimate domain registrars and DDoS enablers.
Verizon's acquisition of Yahoo! remains in doubt.