Security Enhancement in Interactive CAPTCHA
K Soumya, Athira Sasikumar, Sancy P Prakash · IOSR Journal of Computer Engineering · 2014
CAPTCHA stands for Computer Automated Public Turing Test to Tell Computers and HumansApart.It is a defense system against attacks on websites.The paper deals with a variant of conventional CAPTCHA named Interactive CAPTCHA which uses a series of user interactions to solve the CAPTCHA.The proposed system also encrypts the CAPTCHA response send to the server so as to avoid attacks like MITM(Man In The Middle attacks).The system uses a Secure Socket Layer(SSL) connection to transmit the encrypted response to the server providing additional security.Encryption and decryption of CAPTCHA response is done by the Rivest Shamir Adleman(RSA) algorithm using a encryption/decryption key pair.