What we know about Iran's efforts to interfere in U.S. elections

U.S. intelligence agencies said this week that Iran was responsible for hacking into former President Donald Trump's White House campaign. Iran denies the allegations, but in a joint statement, top intel agencies say Iran's efforts to interfere with the upcoming election go beyond just the Trump campaign. CBS News national security contributor Sam Vinograd has more on that and some of the other top national security stories of the week.