Biblio

Security experts often recommend using password-management tools that both store passwords and generate random passwords. However, research indicates that only a small fraction of users use password managers with password generators. Past studies have explored factors in the adoption of password managers using surveys and online store reviews. Here we describe a semi-structured interview study with 30 participants that allows us to provide a more comprehensive picture of the mindsets underlying adoption and effective use of password managers and password-generation features. Our participants include users who use no password-specific tools at all, those who use password managers built into browsers or operating systems, and those who use separately installed password managers. Furthermore, past field data has indicated that users of built-in, browser-based password managers more often use weak and reused passwords than users of separate password managers that have password generation available by default. Our interviews suggest that users of built-in password managers may be driven more by convenience, while users of separately installed tools appear more driven by security. We advocate tailored designs for these two mentalities and provide actionable suggestions to induce effective password manager usage.

Computer security problems often occur when there are disconnects between users’ understanding of their role in computer security and what is expected of them. To help users make good security decisions more easily, we need insights into the challenges they face in their daily computer usage. We built and deployed the Security Behavior Observatory (SBO) to collect data on user behavior and machine configurations from participants’ home computers. Combining SBO data with user interviews, this paper presents a qualitative study comparing users’ attitudes, behaviors, and understanding of computer security to the actual states of their computers. Qualitative inductive thematic analysis of the interviews produced “engagement” as the overarching theme, whereby participants with greater engagement in computer security and maintenance did not necessarily have more secure computer states. Thus, user engagement alone may not be predictive of computer security. We identify several other themes that inform future directions for better design and research into security interventions. Our findings emphasize the need for better understanding of how users’ computers get infected, so that we can more effectively design user-centered mitigations.

Risk homeostasis theory claims that individuals adjust their behaviors in response to changing variables to keep what they perceive as a constant accepted level of risk [8]. Risk homeostasis theory is used to explain why drivers may drive faster when wearing seatbelts. Here we explore whether risk homeostasis theory applies to end-user security behaviors. We use observed data from over 200 participants in a longitudinal in-situ study as well as survey data from 249 users to attempt to determine how user security behaviors and attitudes are affected by the presence or absence of antivirus software. If risk compensation is occurring, users might be expected to behave more dangerously in some ways when antivirus is present. Some of our preliminary data suggests that risk compensation may be occurring, but additional work with larger samples is needed. 

We present an architecture for the Security Behavior Observatory (SBO), a client-server infrastructure designed to collect a wide array of data on user and computer behavior from hundreds of participants over several years. The SBO infrastructure had to be carefully designed to fulfill several requirements. First, the SBO must scale with the desired length, breadth, and depth of data collection. Second, we must take extraordinary care to ensure the security of the collected data, which will inevitably include intimate participant behavioral data. Third, the SBO must serve our research interests, which will inevitably change as collected data is analyzed and interpreted. This short paper summarizes some of our design and implementation benefits and discusses a few hurdles and trade-offs to consider when designing such a data collection system.

Much of the data researchers usually collect about users’ privacy and security behavior comes from short-term studies and focuses on specific, narrow activities. We present a design architecture for the Security Behavior Observatory (SBO), a client-server infrastructure designed to collect a wide array of data on user and computer behavior from a panel of hundreds of participants over several years. The SBO infrastructure had to be carefully designed to fulfill several requirements. First, the SBO must scale with the desired length, breadth, and depth of data collection. Second, we must take extraordinary care to ensure the security and privacy of the collected data, which will inevitably include intimate details about our participants’ behavior. Third, the SBO must serve our research interests, which will inevitably change over the course of the study, as collected data is analyzed, interpreted, and suggest further lines of inquiry. We describe in detail the SBO infrastructure, its secure data collection methods, the benefits of our design and implementation, as well as the hurdles and tradeoffs to consider when designing such a data collection system. 

To help users create stronger text-based passwords, many web sites have deployed password meters that provide visual feedback on password strength. Although these meters are in wide use, their effects on the security and usability of passwords have not been well studied. We present a 2,931-subject study of password creation in the presence of 14 password meters. We found that meters with a variety of visual appearances led users to create longer passwords. However, significant increases in resistance to a password-cracking algorithm were only achieved using meters that scored passwords stringently. These stringent meters also led participants to include more digits, symbols, and uppercase letters. Password meters also affected the act of password creation. Participants who saw stringent meters spent longer creating their password and were more likely to change their password while entering it, yet they were also more likely to find the password meter annoying. However, the most stringent meter and those without visual bars caused participants to place less importance on satisfying the meter. Participants who saw more lenient meters tried to fill the meter and were averse to choosing passwords a meter deemed “bad” or “poor.” Our findings can serve as guidelines for administrators seeking to nudge users towards stronger passwords.