Close. They didn't hack as the title would lead you to believe though, they only tried to inject themselves as valid exit Tor nodes to de-anonymize users.
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I don't use Tor, but for any anonymous system that allows arbitrary exit nodes, you figure any government, such as Russia, China, US, etc... who wants to get these users would inject themselves into the network making themselves exit nodes. This just showed Russia was already trying to do it, we all know the other governments are trying as well.

</tin-foil hat>