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Module 18 Web based Password Cracking Techniques

In cryptanalysis and computer security, password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system. A common approach is to repeatedly try guesses for the password. Another common approach is to say that you have "forgotten" the password and then change it. | Ethical Hacking and Countermeasures Version 6 Module XVIII Web-based Password Cracking Techniques IM c E H News Certified Ethical Hacker NEWS Password-Cracking Chip Causes Security Concerns By ANDREW BRANDT Oct. 24. 2007 A technique for cracking computer passwords using inexpensive off-the-shelf computer graphics hardware is causing a stir in the computer security community. Elcomsoft a software company based in Moscow Russia has filed a US patent for the technique It takes advantage of the massively parallel processing capabilities of a graphics processing unit GPU - the processor normally used to produce realistic graphics for video games. Using an 800 graphics card from nVidia called the GeForce 8800 Ultra Elcomsoft increased the speed of its password cracking by a factor of 25 according to the company s CEO Vladimir Katalov. The toughest passwords including those used to log in to a Windows Vista computer would normally take months of continuous computer processing time to crack using a computer s central processfrig unit CPU . By harnessing a 150 GPU - less powerful than the nVidia 8800 card - Elcomsoft says they can cracked in just three to five days. Less complex passwords can be retrieved in minutes rather than hours or days. It is the way a GPU processes data that provides the speed increase. NVidia spokesman Andrew Humber describes the process using the analogy of searching for words in a book A normal computer processor would read the book starting at page 1 and finishing at page 500 he says. A GPU would take the book tear it into a 100 000 pieces and read all of those pieces at the same tune. Benjamin Jun of Cryptography Research based in San Francisco US says massively parallel processing is ideally suited to the task of breaking passwords. And while concerned about the development Jun also pays tribute to the achievement A number of US have been following advances in those platforms and there s a lot of elegant intelligent design. EC-Council Source .