Common Passwords and Common Words in Passwords

  • Jikai LiEmail author
  • Ethan Zeigler
  • Thomas Holland
  • Dimitris Papamichail
  • David Greco
  • Joshua Grabentein
  • Daan Liang
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 1160)


Passwords often include dictionary words or meaningful strings. Figuring out these words or strings may significantly reduce the number of password guessing. The wordlists used by password cracking software, such as Hashcat, typically include the words from various dictionaries and leaked plain passwords. Is it really necessary to put all dictionary words and leaked passwords into the wordlist? In this work, we use Mac system dictionary and leak as two sample wordlists to check the substrings of over 600 million leaked passwords from different websites. We find only a small portion of words from these two wordlists are used by the leaked passwords. More specifically, about 90,000 out of 235,886 Mac dictionary words and about six millions out of 13 millions unique passwords are used by the leaked passwords. In addition to that, we find that a small portion of unique passwords are shared by a large portion of accounts.


Password Hashcat Dictionary Substring 


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Copyright information

© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Jikai Li
    • 1
    Email author
  • Ethan Zeigler
    • 1
  • Thomas Holland
    • 1
  • Dimitris Papamichail
    • 1
  • David Greco
    • 1
  • Joshua Grabentein
    • 1
  • Daan Liang
    • 2
  1. 1.The College of New JerseyEwingUSA
  2. 2.Department of Civil, Construction and Environmental EngineeringUniversity of AlabamaTuscaloosaUSA

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