After removing passwords shorter than four characters and longer than 18, the researchers found that 51% of “common” passwords could be cracked in less than a minute. Two-thirds (65%) could be cracked in less than an hour, 71% could be cracked in under a day, and 81% could be cracked in less than a month. Even seven-character passwords with numbers, upper and lowercase letters, and symbols could be cracked in under six minutes.
