But privately, per the Times, those same officials reportedly say they still aren't sure exactly what was or was not taken.

There are concerns that the SVR - which the U.S. intelligence agency and Secretary of State Mike Pompeo are confident was behind the breach, despite President Trump suggesting China may have been involved instead of Moscow - was able to get its hands on delicate, albeit unclassified information from victims like the Federal Energy Regulatory Commission. For example, it's reportedly possible the hackers accessed Black Start, the detailed technical blueprints for how the U.S. would restore power if there was a major blackout. If that was indeed the case, Russia would theoretically have a list of systems it could target to keep power from turning back on.

The Times report sheds more light on the cyberattack, which may not be fully understood for months or even years. Some of the revelations include the fact that the hack appears to have been much broader in scope than originally thought and that the hackers "managed their intrusion from servers inside" the U.S. by "exploiting legal prohibitions on the National Security Agency."