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CAPTCHA Cracker using MATLAB

International Journal of Computer Applications
Foundation of Computer Science (FCS), NY, USA
Year of Publication: 2016
Kunal Kathrani, Piyush Agrawal, Khushi Khanchandani

Kunal Kathrani, Piyush Agrawal and Khushi Khanchandani. Article: CAPTCHA Cracker using MATLAB. International Journal of Computer Applications 139(13):20-23, April 2016. Published by Foundation of Computer Science (FCS), NY, USA. BibTeX

	author = {Kunal Kathrani and Piyush Agrawal and Khushi Khanchandani},
	title = {Article: CAPTCHA Cracker using MATLAB},
	journal = {International Journal of Computer Applications},
	year = {2016},
	volume = {139},
	number = {13},
	pages = {20-23},
	month = {April},
	note = {Published by Foundation of Computer Science (FCS), NY, USA}


There is a lot of activity over the internet. Be it, posting a comment on someone’s blog or making a Gmail account or booking a ticket online. But with that also comes the problem of spamming. “Completely Automated Public Turing test to tell Computers and Humans Apart” (CAPTCHA) [8] which are the twisted words that block the entries of bots on website. CAPTHCAs can effectively test if the user is human or machine. Hence it is of great importance that CAPTCHA is well checked for its vulnerability against such attacks. So this paper presents this medium to check the strength of CAPTCHA against the written CAPTCHA cracking code. This can be used by the web developers implementing CAPTCHA, to check well in advance how secure is the CAPTCHA used in their software.


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  8. Christoph Fritsch, Michael Netter, Andreas Reisser, and Günther Pernul, Attacking Image Recognition Captchas A Naive but Effective Approach
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  11. Jeff Yan, Ahmad Salah El Ahmad Breaking Visual CAPTCHAs with Naïve Pattern Recognition Algorithms.


CAPTCHA, OCR, Image Processing, MATLAB, Turing Test, CAPTCHA Cracking.