1. password (Unchanged) (Down 6) (Unchanged)14. sunshine (Up 1) (Unchanged)15. master (Down 1) 4. abc123 (Up 1) (Up 4) 5. qwerty (Down 1)17. welcome (New) 6. monkey (Unchanged)18. shadow (Up 1) 7. letmein (Up 1)19. ashley (Down 3) 8. dragon (Up 2)20. football (Up 5) (Up 3)21. jesus (New) 10. baseball (Up 1)22. michael (Up 2) 11. iloveyou (Up 2)23. ninja (New) 12. trustno1 (Down 3)24. mustang (New) 25. password1 (New) compiled from files containing millions of stolen passwords posted online by hackers.

*eight hundred thirty nine quadrillion, two hundred ninety nine trillion, three hundred sixty five billion, eight hundred sixty eight million, three hundred forty thousand, two hundred twenty four

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ItemMean Number of Sites105.7 Number of Unique IDs6.6 Number of Unique passwords4.7 Number of Unique log-in credentials11.8 ID re-use ratio19.1 Password re-use ratio29.2 Log-in credentials re-use10.5 % of used unique log-in credentials45.6%

ItemMean Inclusiveness0.94Use the same log-in credentials Largest component nd largest component (cumulative) 3 rd largest component (cumulative) Vulnerability Index most frequently used log-in combinations use in 81% of sites vs unique log-in credentials VI = expected proportion of sites subject to potential breaches if a breach at one site occurs Larger values of VI indicate higher levels of vulnerability

Fixes: Binding Mechanisms Allow a new site/app to remind in the future to update my credentials Secure Defaults I say use a password manger User Friendliness Make credentials easier for humans Face recognition vs character string memorization Incentives Discount for using strong passwords Costs for not – Why are CC companies responsible for your lack of a strong password?

Use Password Manager 1Password Roboform Password Based Key Derivation Function Version 2 (PBKDFV2) Systems using PBKDFV2 Copyright Pearson Prentice-Hall

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"There [were] a lot of variations of the word pass and root and also hax was used many times, but if I omit one common 4- letter word, the most frequently used word in this dictionary is hack," Hýža wrote. "It is worth mentioning that many PHP shells I analysed had only default passwords like r57, c99, password or yourpass."