An official report that circulated through the intelligence community alleges that agents of the Russian government sent Twitter messages carrying malware to more than 10,000 Defense Dept. employees, reports TIME's Massimo Calabresi.
How they did it: The messages pinpointed specific interests of the targets to entice users to click on the forwarded link. The link would then take them to a Russian-run server that would download software enabling hackers to gain control of the user's phone or computer and Twitter account.
The threat: As Calabresi points out, the hack represents a new kind of cyber threat, beyond what took place in the 2016 campaign. Now that Russia has found a way to take over Twitter accounts, they could cause serious damage by tweeting in real-time from the handle of, say, a Pentagon employee.