Arun Vishwanath is a technologist who studies the people problem of cybersecurity. The views expressed in this commentary are his own. View more opinion at CNN.

(CNN) The continued prosecution of "all the President's men" does little to stop the Russians from attempting to influence America's upcoming midterm elections. And reports from Missouri to California suggest they are already looking for our cyber weaknesses to exploit.

Chief among their tools: spear phishing, which are emails containing hyperlinks to fake websites. Russians used this method to hack into the Democratic National Committee (DNC) emails and set in motion their 2016 influence campaign.

After two years of congressional hearings, indictments and investigations, spear phishing not only continues to be the most common attack used by hackers, but the Russians are still trying to use it against us.

That's because the method has become even more virulent, thanks to the availability of sophisticated malware, some stolen from intelligence agencies; troves of people's personal information from previous breaches; and ongoing developments in machine learning that can deep-dive into this data and craft highly effective attacks.

Just last week, Microsoft blocked six fake websites that were likely to be used by the same Russian intelligence unit responsible for the 2016 DNC hack to spear phish American targets.