Password Cracking Based on Learned Patterns From Disclosed Passwords

[[abstract]]Password-based authentication systems are still the most commonly used mechanism for protecting sensitive information despite being vulnerable to dictionary based attacks. To guard against such attacks, many organizations enforce complicated password-creation rules and require that passwords include numeric and special characters. This study demonstrates that as long as passwords are not difficult to remember, they remain vulnerable to “smart dictionary” attacks. In this study, a password analysis platform is developed to formally analyze commonly used passwords and identify frequently used password patterns and their associated probabilities. Based upon these patterns, we establish a model consisting of a Training set, a Dictionary set and a Testing set (TDT model) to generate probabilistic passwords sorted in decreasing order. The model can be used to dramatically reduce the size of the password space to be searched. Simulation results show that the number of passwords cracked using the TDT model is 1.43 and 2.5 times higher compared with the John-the-Ripper attack and Brute-force attack, respectively. We also design a hybrid password cracking system combining different attacks to verify the effectiveness of the proposed method. After applying the TDT model, the number of passwords cracked increased by up to 273%.[[journaltype]]國外[[incitationindex]]EI[[booktype]]紙本[[countrycodes]]JP

Password Cracking Based on Special Keyboard Patterns

[[abstract]]Passwords are still the most commonly used mechanism for user authentication. However, they are vulnerable to dictionary attacks. In order to guard against such attacks, administrative policies force the use of complex rules to create passwords. One commonly used "trick" is to use keyboard patterns, i.e., key patterns on a keyboard, to create passwords that conform to the complex rules. This paper proposes an efficient and effective method to attack passwords generated from some special keyboard patterns. We create a framework to formally describe the commonly used keyboard patterns of adjacent keys and parallel keys, called AP patterns, to generate password databases. Our simulation results show that the password space generated using AP patterns is about 244.47 times smaller than that generated for a brute-force attack. We also design a hybrid password cracking system consisting of different attacking methods to verify the effectiveness. Our results show that the number of passwords cracked increases up to 114% on average than without applying AP patterns.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙

Thermodynamically optimal whole-genome tiling microarray design and validation

Additional file 2. Assembled genome sequences for E. coli MG1655 and Agrobacterium tumefaciens C58. Two FASTA files containing the assembled genomic sequences are provided in this compressed ZIP archive