Abstract. Many users routinely log in to their system with system administrator privileges. This is especially true of home users. The advantage of this setup is that these users c...
Dinan Gunawardena, Jacob Scott, Alf Zugenmaier, Au...
CAPTCHAs protect online resources and services from automated access. From an attacker’s point of view, they are typically perceived as an annoyance that prevents the mass creat...
Manuel Egele, Leyla Bilge, Engin Kirda, Christophe...
Many financial institutions have deployed CAPTCHAs to protect their services (e.g., e-banking) from automated attacks. In addition to CAPTCHAs for login, CAPTCHAs are also used to...
Shujun Li, S. Amier Haider Shah, M. Asad Usman Kha...
We introduce captcha, an automated test that humans can pass, but current computer programs can’t pass: any program that has high success over a captcha can be used to solve an u...
Luis von Ahn, Manuel Blum, Nicholas J. Hopper, Joh...
We propose IMAGINATION (IMAge Generation for INternet AuthenticaTION), a system for the generation of attack-resistant, user-friendly, image-based CAPTCHAs. In our system, we prod...