Title
Measuring password guessability for an entire university
Abstract
Despite considerable research on passwords, empirical studies of password strength have been limited by lack of access to plaintext passwords, small data sets, and password sets specifically collected for a research study or from low-value accounts. Properties of passwords used for high-value accounts thus remain poorly understood. We fill this gap by studying the single-sign-on passwords used by over 25,000 faculty, staff, and students at a research university with a complex password policy. Key aspects of our contributions rest on our (indirect) access to plaintext passwords. We describe our data collection methodology, particularly the many precautions we took to minimize risks to users. We then analyze how guessable the collected passwords would be during an offline attack by subjecting them to a state-of-the-art password cracking algorithm. We discover significant correlations between a number of demographic and behavioral factors and password strength. For example, we find that users associated with the computer science school make passwords more than 1.5 times as strong as those of users associated with the business school. while users associated with computer science make strong ones. In addition, we find that stronger passwords are correlated with a higher rate of errors entering them. We also compare the guessability and other characteristics of the passwords we analyzed to sets previously collected in controlled experiments or leaked from low-value accounts. We find more consistent similarities between the university passwords and passwords collected for research studies under similar composition policies than we do between the university passwords and subsets of passwords leaked from low-value accounts that happen to comply with the same policies.
Year
DOI
Venue
2013
10.1145/2508859.2516726
ACM Conference on Computer and Communications Security
Keywords
Field
DocType
entire university,state-of-the-art password,password strength,stronger password,research university,research study,considerable research,low-value account,business school,password guessability,complex password policy,university password,passwords,password security,authentication
Internet privacy,Password cracking,Password strength,Computer science,Computer security,Password psychology,One-time password,Password policy,Password,Cognitive password,Plaintext
Conference
Citations 
PageRank 
References 
80
2.16
32
Authors
9
Name
Order
Citations
PageRank
Michelle L. Mazurek1105957.67
Saranga Komanduri2109541.21
Timothy Vidas371538.49
Lujo Bauer42460120.71
Nicolas Christin52133126.02
Lorrie Faith Cranor66767515.80
Patrick Gage Kelley7167979.74
Richard Shay8107343.90
Blase Ur997348.81