12 search results - page 1 / 3 » Attacks and design of image recognition CAPTCHAs |
ACSAC
2010
IEEE
13 years 2 months ago
2010
IEEE
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...
CCS
2010
ACM
13 years 4 months ago
2010
ACM
We systematically study the design of image recognition CAPTCHAs (IRCs) in this paper. We first review and examine all IRCs schemes known to us and evaluate each scheme against th...
CCS
2010
ACM
13 years 7 months ago
2010
ACM
In this paper, we propose a new form of image-based CAPTCHA we term "scene tagging". It tests the ability to recognize a relationship between multiple objects in an imag...
SP
2010
IEEE
13 years 8 months ago
2010
IEEE
—Captchas are designed to be easy for humans but hard for machines. However, most recent research has focused only on making them hard for machines. In this paper, we present wha...
WWW
2009
ACM
14 years 5 months ago
2009
ACM
We present a new CAPTCHA which is based on identifying an image's upright orientation. This task requires analysis of the often complex contents of an image, a task which hum...