In October, news broke that the CIA was preparing options to launch a cyberattack against Russia following revelations that the country was likely behind hacks at the Democratic National Committee earlier this summer. Now, a source has told NBC News that the US has penetrated key Russian systems, and will be ready to take action in case the country decides to interfere with next week’s elections.

The US is preparing in case it is "attacked in a significant way"

The systems allegedly include some of Russia’s telecommunications networks, its electrical power grid, and command systems at the Kremlin. NBC reported that the preparations are being made in the event that the US is "attacked in a significant way," according to an anonymous intelligence official and top secret documents that the network had reviewed.

While US election infrastructure has significant flaws with outdated voting machines and voter data, the decentralized nature of the election makes it much harder for attackers to outright change the final outcome.

Digital security has become a concern during this election cycle, although NBC notes that the officials it spoke with "do not expect Russia to attack critical infrastructure," although they do expect some "cyber mischief," such as releases of fake documents and digital misinformation campaigns.