Press Esc to close
Friday 18 August 2017
News updated at 2:45 AM IST

Now, 'inkblot' passwords for unbreakable security

Washington, Nov 8, 2013 (PTI) 20:42 IST
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 fruit vendor, holding an umbrella, waits for customers at a street in Kolkata on Thursday.

A fruit vendor, holding an umbrella, waits for customers at a street in Kolkata on Thursday.

Ranbir Kapoor, actor and co-owner Mumbai City FC meeting fans during the Indian Super League...

Ranbir Kapoor, actor and co-owner Mumbai City FC meeting fans during the Indian Super League...

India's Ramandeep Singh in action against Austria in their final encounter of the Europe Tour...

India's Ramandeep Singh in action against Austria in their final encounter of the Europe Tour...

People from Parsi community cut a cake to celebrate their new year, Navroze, in Ahmedabad on ...

People from Parsi community cut a cake to celebrate their new year, Navroze, in Ahmedabad on ...

Nail artist Murari Aditya, 75 years, shows his 38 inch long nails, at his residence in Kolkata ...

Nail artist Murari Aditya, 75 years, shows his 38 inch long nails, at his residence in Kolkata ...

The first batch of Dasara elephants being welcomed on their arrival at Mysuru Palace on Thursday.

The first batch of Dasara elephants being welcomed on their arrival at Mysuru Palace on Thursday.

: Participants struggle during a greased-pole climbing competition held as a part of independence...

: Participants struggle during a greased-pole climbing competition held as a part of independence...

Activist Irom Sharmila with her husband British citizen Desmond Coutinha after getting married...

Activist Irom Sharmila with her husband British citizen Desmond Coutinha after getting married...

A visitor looks at an art installation, symbolizing the partition of India and Pakistan...

A visitor looks at an art installation, symbolizing the partition of India and Pakistan...

Artist Sunil Paul gives finishing touches on a statue of St. Mother Teresa at his studio...

Artist Sunil Paul gives finishing touches on a statue of St. Mother Teresa at his studio...

Like us on Facebook

Copyright 2017, The Printers (Mysore) Private Ltd., 75, M.G Road, Post Box 5331, Bengaluru - 560001
Tel: +91 (80) 25880000 Fax No. +91 (80) 25880523
Powered by Yodasoft Technologies Pvt. Ltd.