All about uncertainties and traps: Statistical oracle-based attacks on a new CAPTCHA protection against oracle attacks
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چکیده
منابع مشابه
An oracle-based attack on CAPTCHAs protected against oracle attacks
CAPTCHAs/HIPs are security mechanisms that try to prevent automatic abuse of services. They are susceptible to learning attacks in which attackers can use them as oracles. Kwon and Cha presented recently a novel algorithm that intends to avoid such learning attacks and “detect all bots” [6]. They add uncertainties to the grading of challenges, and also use trap images designed to detect bots. T...
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ژورنال
عنوان ژورنال: Computers & Security
سال: 2020
ISSN: 0167-4048
DOI: 10.1016/j.cose.2020.101758