san francisco russian hack 2016 u.s. election include sophisticate target state officials responsible voter roll vote procedures accord top secret u.s. intelligence document leak publish week reveal another potential method attempt interference vote month-old national security agency document outline activities include impersonate election software vendor send trick email 100 state election officials analysts nsa believe hackers work russian military general staff main intelligence directorate gru accord document document publication monday intercept news outlet focus security issue receive particular attention intelligence contractor reality leigh winner charge day leak u.s. intelligence agencies previously say kremlin try influence election outcome favor republican candidate donald trump leak campaign hack email democratic party officials aim discredit democratic candidate hillary clinton new revelations suggest u.s. investigators also still probe direct attempt attack election federal official confirm case however evidence hackers able manipulate vote vote tally document say least one employee software vendor account compromise cover whether elections officials also successfully compromise compromise officials hackers could plant malicious software capture proof infection suggest fraud clinton behalf nov. election experts say goal disrupt election need pick winner actually tamper tally result say matt blaze university pennsylvania computer science professor write security vote machine simply cast doubt legitimacy result could achieve goals government-sponsored hack campaign say u.s. intelligence officials previously state russian intelligence access multiple election officials say compromise machine involve vote tally say sophisticate extensive effort work russian president vladimir putin strongly deny russian government involvement election hack though say last week patriotic russians could involve trump deny collusion spear-phishing elections officials newly leak nsa report say hackers use so-called spear-phishing techniques election officials try convince target click link email seem come legitimate correspondents report describe one phishing campaign hit state officials week election give locations say successful although may many others security experts say one come late game would likely sow chaos try alter vote count report say hackers try accomplish investigation computers people target would jurisdiction fbi fbi spokeswoman decline comment tuesday office special counsel robert mueller investigate possible collusion trump campaign officials russian government bait use spear-phishing campaign involve software manage voter registration roll hackers might consider delete record force officials turn legitimate voters away say elections technology security expert alex halderman university michigan wide report mass rejections voters perhaps plan abandon prove hard execute say also possible idea get onto machine officials oversee registration vote software elections run counties unite state depend county configuration security practice separate could access potentially every aspect list register voters vote machine firmware machine ballot present software control final tally blaze say holy grail attacker would want compromise members congress say hop learn hack attempt important american people understand russian attempt break number state vote process talk fall broad-based democrat mark warner vice chairman senate intelligence committee tell reporters hope come days get information that u.s. spy agencies probe another flank russian hack