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Enhancing the Security of Image CAPTCHAs Through Noise Addition [chapter]

David Lorenzi, Emre Uzun, Jaideep Vaidya, Shamik Sural, Vijayalakshmi Atluri
2015 IFIP Advances in Information and Communication Technology  
Image CAPTCHAs provide an alternative that is often preferred to text-based implementations. However, Image CAPTCHAs have their own set of security and usability problems.  ...  To evaluate the usability/security tradeoff, we conduct a user study to determine if the method can provide "usable" images that meet our security requirements -thus improving the overall security provided  ...  Through this transformation, image CAPTCHAs can again become a viable alternative to text based CAPTCHAs having a similar level of security while providing a superior level of usability.  ... 
doi:10.1007/978-3-319-18467-8_24 fatcat:pcoz65gqyvgvddrf4lfwvg3knu

Counteracting Dark Web Text-Based CAPTCHA with Generative Adversarial Learning for Proactive Cyber Threat Intelligence [article]

Ning Zhang, Mohammadreza Ebrahimi, Weifeng Li, Hsinchun Chen
2022 arXiv   pre-print
In the dark web, CAPTCHA images are meticulously designed with additional background noise and variable character length to prevent automated CAPTCHA breaking.  ...  To eliminate the need for human involvement, the proposed framework utilizes Generative Adversarial Network (GAN) to counteract dark web background noise and leverages an enhanced character segmentation  ...  ACKNOWLEDGMENTS This material is based upon work supported by the National Science Foundation (NSF) under the following grants: SaTC-1936370, CICI-1917117, and SFS-1921485.  ... 
arXiv:2201.02799v2 fatcat:nepnavt6onaf7ncinm2x6ar5ey

Design of Secure Multilingual CAPTCHA Challenge

M. Tariq Banday, Shafiya Afzal Sheikh
2015 International Journal of Web Portals  
The results of experiments, security tests, and users study with the CAPTCHA tests generated through the proposed technique have validated its design, security, usability, and accessibility.  ...  It discusses the design, algorithm, pseudo code, and working of a secure multilingual text CAPTCHA script having desired security, accessibility and usability features.  ...  To make these challenges difficult for bots to break, security of CAPTCHA tests were enhanced by adding deformation, distortion, random image backgrounds, noise, etc.  ... 
doi:10.4018/ijwp.2015010101 fatcat:5m3rv4p47bbbvikjqrqmkmjyaq

Augmented Data Selector to Initiate Text-Based CAPTCHA Attack

Aolin Che, Yalin Liu, Hong Xiao, Hao Wang, Ke Zhang, Hong-Ning Dai, Ting Chen
2021 Security and Communication Networks  
Meanwhile, the data augmentor uses four different image noises to generate different CAPTCHA images.  ...  To investigate this issue, we propose a simple, generic, and effective preprocessing approach to filter and enhance the original CAPTCHA data set so as to improve the accuracy of the previous attack methods  ...  [1] firstly discuss the use of the dedicated-designed CAPTCHA schemes to prevent the attack from robots and thereby enhance network security.  ... 
doi:10.1155/2021/9930608 fatcat:lagesev6xzg2vmeddtz6ccjomy

Generation of Variant Random Order (VRO) in Text Graphics Color CAPTCHA for Enhancing Web Security Protection

S. Pradeep Kumar, R. Ramachandaran, A. Saravanan
2016 Indian Journal of Science and Technology  
Findings: Applications: This type of techniques helps the proposed system to display the CAPTCHA with additional security in major application areas such as health services, military services and banking  ...  To overcome this problem, we introduce a Variant Random Order (VRO) in text-graphics color CAPTCHA approach for enhancing web security.  ...  This image will have some noise due to the horizontal or cross lines are cracked in the CAPTCHA characters 3 .  ... 
doi:10.17485/ijst/2016/v9i10/88893 fatcat:d5kmtpg6e5d4vlopzq33gj6wzm

Robust CAPTCHA Image Generation Enhanced with Adversarial Example Methods

Hyun KWON, Hyunsoo YOON, Ki-Woong PARK
2020 IEICE transactions on information and systems  
We used the CAPTCHA image provided by python as the dataset and Tensorflow as the machine learning library.  ...  In this paper, we propose a method to generate CAPTCHA images by using the fast-gradient sign method (FGSM), iterative FGSM (I-FGSM), and the DeepFool method.  ...  In addition, we analyzed the performance of the proposed method by using the CAPTCHA image dataset provided by Python.  ... 
doi:10.1587/transinf.2019edl8194 fatcat:i7upkzzdtndcbe5z4a3kztcu5a

Web security through improvised image based CAPTCHA

R. Murugan, Tejasri. P, Nobesh Reddy, G. Dinesh
2017 International Journal of Engineering & Technology  
The user needs to spot the image to pass the test. A flag will be counting the number of times the user failed the test and depending on the number of failure attempts the user is judged.  ...  It is a question-based image-oriented technique where a question comprising of keywords is posed along with four different images out of which only one image has relation with all the keywords.  ...  It is image of distorted text/numbers and addition to with some background noise or clutter. The content is generated randomly either text or alphanumeric.  ... 
doi:10.14419/ijet.v7i1.1.9481 fatcat:gvpemiswergmvdoael6qb2frsy

Enhancing security against hard AI problems in user authentication using CAPTCHA as graphical passwords

S. Murugavalli, S.A.K. Jainulabudeen, G. Senthil Kumar, D. Anuradha
2016 International Journal of Advanced Computer Research  
Textual CAPTCHAs [10] as shown in Figure 1 are designed as distorted text images and sometimes with noise addition which are identified by humans easily.  ...  The most widely used CAPTCHAs are the textual CAPTCHA, displayed as a distorted textual image along with noise for visually impaired ones.  ... 
doi:10.19101/ijacr.2016.624001 fatcat:y5ntcgd22rahpkhttmp6qxu6mi

A Novel Design of Audio CAPTCHA for Visually Impaired Users

Mrim Alnfiai
2020 Zenodo  
To increase the security of HearAct, it is necessary to increase the number of sounds in the CAPTCHA.  ...  CAPTCHAs are widely used by web applications for the purpose of security and privacy.  ...  In addition, I will compare the proposed solution with other existing audio CAPTCHAs to measure the correlations between them.  ... 
doi:10.5281/zenodo.4006148 fatcat:2fpxy4j225ehnlnfyexrd273wu

Breaking e-banking CAPTCHAs

Shujun Li, S. Amier Haider Shah, M. Asad Usman Khan, Syed Ali Khayam, Ahmad-Reza Sadeghi, Roland Schmitz
2010 Proceedings of the 26th Annual Computer Security Applications Conference on - ACSAC '10  
In addition to CAPTCHAs for login, CAPTCHAs are also used to prevent malicious manipulation of e-banking transactions by automated Man-in-the-Middle (MitM) attackers.  ...  Despite serious financial risks, security of e-banking CAPTCHAs is largely unexplored. In this paper, we report the first comprehensive study on e-banking CAPTCHAs deployed around the world.  ...  Unfortunately, our attacks can be easily enhanced to tolerate lossy compression by adding an additional noise filter.  ... 
doi:10.1145/1920261.1920288 dblp:conf/acsac/LiSKKSS10 fatcat:ja35g43h4rardgrowo2sevolpi


Sushma Yalamanchili, Kameswara Rao
2011 Zenodo  
The design and implementation of CAPTCHAs fall in the realm of Artificial Intelligence. We aim to utilize CAPTCHAs as a tool to improve the security of Internet based applications.  ...  Our selection of Devanagari script-based CAPTCHA is based on the fact that it is used by a large number of Indian languages including Hindi which is the third most spoken language.  ...  Security of an existing text CAPTCHA is enhanced by systematically adding noise and distortion, and arranging characters more tightly [3, 4] .  ... 
doi:10.5281/zenodo.3366494 fatcat:z74e2x4axnggraautwezp42rb4

A Framework for Devanagari Script-based Captcha [article]

Sushma Yalamanchili, M.Kameswara Rao
2011 arXiv   pre-print
The design and implementation of CAPTCHAs fall in the realm of Artificial Intelligence. We aim to utilize CAPTCHAs as a tool to improve the security of Internet based applications.  ...  Our selection of Devanagari script-based CAPTCHA is based on the fact that it is used by a large number of Indian languages including Hindi which is the third most spoken language.  ...  Security of an existing text CAPTCHA is enhanced by systematically adding noise and distortion, and arranging characters more tightly [3, 4] .  ... 
arXiv:1109.0132v1 fatcat:6ar7g4pou5e3bktjbvlkdb72qi

CAPTCHA Image Generation: Two-Step Style-Transfer Learning in Deep Neural Networks

Hyun Kwon, Hyunsoo Yoon, Ki-Woong Park
2020 Sensors  
The method utilizes the style transfer method, and creates a new image, called a style-plugged-CAPTCHA image, by incorporating the styles of other images while keeping the content of the original CAPTCHA  ...  To prevent such automated attacks, CAPTCHAs are widely used as a security solution.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s20051495 pmid:32182829 fatcat:u24ahe5kovh33alyuc5gihnss4

A Proposal of Four-Panel Cartoon CAPTCHA: The Concept

Takumi Yamamoto, Tokuichiro Suzuki, Masakatsu Nishigaki
2010 2010 13th International Conference on Network-Based Information Systems  
However, as many researchers have already reported, conventional CAPTCHA could be overcome by state-of-the-art malware since the capabilities of computers are approaching those of humans.  ...  In addition, it is also important to keep in mind that answering CAPTCHA is an added annoyance for users, who feel troublesome to prove that they are human at every Web access.  ...  ACKNOWLEDGEMENTS This research was subsidized in part by a research grant from the Secom Science and Technology Foundation.  ... 
doi:10.1109/nbis.2010.31 dblp:conf/nbis/YamamotoSN10 fatcat:4khzh6wfubcr7gzkgkgbsvogpa

A Survey and Analysis of Current CAPTCHA Approaches

Narges Roshanbin, James Miller
2013 Journal of Web Engineering  
In this paper, we introduce current CAPTCHAs and attacks against them; we investigate the robustness and usability of current CAPTCHAs and discuss ideas to develop more robust and usable CAPTCHAs.  ...  Lack of security and usability in CAPTCHAs designed to protect popular websites such as Gmail and Yahoo mail, with almost 500 million users in July 2011, would cause huge problems.  ...  This CAPTCHA is convenient for users. In addition, since the required processing time in this CAPTCHA is relatively high, it is more secure.  ... 
dblp:journals/jwe/RoshanbinM13 fatcat:xy5pvkvnb5calkqu6ythkqiljy
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