Proceedings ArticleDOI
Text-based CAPTCHA strengths and weaknesses
Elie Bursztein,Matthieu Martin,John C. Mitchell +2 more
- pp 125-138
TLDR
It is found that 13 current visual CAPTCHAs based on distorted characters that are augmented with anti-segmentation techniques from popular web sites are vulnerable to automated attacks.Abstract:
We carry out a systematic study of existing visual CAPTCHAs based on distorted characters that are augmented with anti-segmentation techniques. Applying a systematic evaluation methodology to 15 current CAPTCHA schemes from popular web sites, we find that 13 are vulnerable to automated attacks. Based on this evaluation, we identify a series of recommendations for CAPTCHA designers and attackers, and possible future directions for producing more reliable human/computer distinguishers.read more
Citations
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Journal ArticleDOI
Machine learning
TL;DR: Machine learning addresses many of the same research questions as the fields of statistics, data mining, and psychology, but with differences of emphasis.
Journal ArticleDOI
A generative vision model that trains with high data efficiency and breaks text-based CAPTCHAs
Dileep George,Wolfgang Lehrach,Ken Kansky,Miguel Lázaro-Gredilla,Christopher Laan,Bhaskara Marthi,Xinghua Lou,Zhaoshi Meng,Yi Liu,Huayan Wang,Alexander Lavin,D. Scott Phoenix +11 more
TL;DR: This work introduces recursive cortical network (RCN), a probabilistic generative model for vision in which message-passing–based inference handles recognition, segmentation, and reasoning in a unified manner and outperforms deep neural networks on a variety of benchmarks while being orders of magnitude more data-efficient.
Book ChapterDOI
HelDroid: Dissecting and Detecting Mobile Ransomware
TL;DR: HelDroid is presented, a fast, efficient and fully automated approach that recognizes known and unknown scareware and ransomware samples from goodware, based on detecting the "building blocks" that are typically needed to implement a mobile ransomware application.
The end is nigh: generic solving of text-based CAPTCHAs
TL;DR: The effectiveness and universality of the results suggests that combining segmentation and recognition is the next evolution of catpcha solving, and that it supersedes the sequential approach used in earlier works.
Proceedings ArticleDOI
Yet Another Text Captcha Solver: A Generative Adversarial Network Based Approach
Guixin Ye,Zhanyong Tang,Dingyi Fang,Zhanxing Zhu,Yansong Feng,Pengfei Xu,Xiaojiang Chen,Zheng Wang +7 more
TL;DR: This paper presents a generic, yet effective text captcha solver based on the generative adversarial network and demonstrates that the attack is generally applicable and can bypass the advanced security features employed by most modern text captcha schemes.
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