Friday 25 April 2014
News updated at 12:39 PM IST
Weather
Max: 34.6°C
Min : 22.7°C
In Bangalore
Generally cloudy

Now, 'inkblot' passwords for unbreakable security

Washington, Nov 8, 2013 (PTI)

 Scientists, including one of India-origin, claim to have developed a new 'inkblot' password system that could provide near-unbreakable layer of security against on-line password thefts.

The new password system called GOTCHA developed at the Carnegie Mellon University could secure high-value information such as bank accounts – even if the password leaks as part of a large-scale site breach.

To create a GOTCHA, a user chooses a password and a computer then generates several random, multi-coloured inkblots.

The user describes each inkblot with a text phrase. These phrases are then stored in a random order along with the password.


When the user returns to the site and signs in with the password, the inkblots are displayed again along with the list of descriptive phrases; the user then matches each phrase with the appropriate inkblot.

"These are puzzles that are easy for a human to solve, but hard for a computer to solve, even if it has the random bits used to generate the puzzle," said Jeremiah Blocki, who worked on the system along with professor Manuel Blum, and Anupam Datta, associate professor of computer science.

These puzzles would prove significant when security breaches of websites result in the loss of millions of user passwords - a common occurrence that has plagued such companies as LinkedIn, Sony and Gawker.

These passwords are stored as cryptographic hash functions, in which passwords of any length are converted into strings of bits of uniform length.

A thief can't readily decipher these hashes, but can mount what's called an automated offline dictionary attack.

Computers today can evaluate as many as 250 million possible hash values every second, Blocki noted.

Given the continued popularity of easy passwords, such as "123456" or "password," it's not always difficult to crack these hashes. But even hard passwords are vulnerable to the latest brute force methods, Blocki said.

In the case of a GOTCHA, however, a computer programme alone wouldn't be enough to break into an account.

"To crack the user's password offline, the adversary must simultaneously guess the user's password and the answer to the corresponding puzzle," Datta said.

"A computer can't do that alone. And if the computer must constantly interact with a human to solve the puzzle, it no longer can bring its brute force to bear to crack hashes," said Datta.
Because the user's descriptive phrases for inkblots are stored, users don't have to memorise their descriptions, but have to be able to pick them out from a list. 

Go to Top

Photo Gallery
A digital image called 'Venus, 1985' created by Andy Warhol retrieved from disk 1998.3.2129.3.22...

A digital image called 'Venus, 1985' created by Andy Warhol retrieved from disk 1998.3.2129.3.22...

Crew members of Colombian-registered sailing ship Gloria stand on the ship's masts during a...

Crew members of Colombian-registered sailing ship Gloria stand on the ship's masts during a...

A rainbow appears over the sky of the city of Sao Paulo April 24, 2014. Sao Paulo is one of the...

A rainbow appears over the sky of the city of Sao Paulo April 24, 2014. Sao Paulo is one of the...

27 year old white polar bear Uslada shakes off water in her pool at the Leningrad Zoo in St...

27 year old white polar bear Uslada shakes off water in her pool at the Leningrad Zoo in St...

U.S. President Barack Obama waves from Air Force One as he departs Haneda International Airport...

U.S. President Barack Obama waves from Air Force One as he departs Haneda International Airport...

Singer-songwriter, Leslie Grace arrives at the 2014 Billboard Latin Music Awards on Thursday...

Singer-songwriter, Leslie Grace arrives at the 2014 Billboard Latin Music Awards on Thursday...

A model of a pink fisherman and bicycle are positioned on a rock in the Irish Sea near the...

A model of a pink fisherman and bicycle are positioned on a rock in the Irish Sea near the...

Actress Emma Stone arrives for 'The Amazing Spider-Man 2' premiere in New York April 24, 2014...

Actress Emma Stone arrives for 'The Amazing Spider-Man 2' premiere in New York April 24, 2014...

A girl leaps over headstones at the Jakarta War Cemetery following the ANZAC Day dawn service in...

A girl leaps over headstones at the Jakarta War Cemetery following the ANZAC Day dawn service in...

A fire-fighter walks past a school bus leaning against a eucalyptus tree after it veered off the...

A fire-fighter walks past a school bus leaning against a eucalyptus tree after it veered off the...

Copyright 2014, The Printers (Mysore) Private Ltd., 75, M.G Road, Post Box 5331, Bangalore - 560001
Tel: +91 (80) 25880000 Fax No. +91 (80) 25880523