Long passwords are good, but too much length can be a DoS hazard

For more than a year, Ars has advised readers to use long, randomly generated passwords to protect their digital assets. Now comes definitive proof that too much password length can be detrimental to security.

It comes in the form of just-patched vulnerability in the Django Web development framework. By default, it uses the PBKDF2 algorithm to transform plain-text passwords into long strings called cryptographic hashes. Like scrypt and bcrypt, it's one of the most secure ways websites can store "at rest" passwords, because it passes them through multiple hashing rounds that significantly increase the time and computational resources required. In the event of a breach that spills a large password database, the additional effort can literally add centuries to the process of cracking the raw passwords.

But as Django developers have learned, this enhanced security can be a double-edged blade. In an advisory posted Monday they explained why:

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Fatal crypto flaw in some government-certified smartcards makes forgery a snap

As many of 10,000 of these smartcards may provide little or no cryptographic protection despite receiving two internationally recognized certifications.

Raising troubling questions about the reliability of government-mandated cryptography certifications used around the world, scientists have unearthed flaws in Taiwan's secure digital ID system that allow attackers to impersonate some citizens who rely on it to pay taxes, register cars, and file immigration papers.

The crippling weaknesses uncovered in the Taiwanese Citizen Digital Certificate program cast doubt that certifications designed to ensure cryptographic protections used by governments and other sensitive organizations can't be circumvented by adversaries, the scientists reported in a research paper scheduled to be presented later this year at the Asiacrypt 2013 conference in Bangalore, India. The flaws may highlight shortcomings in similar cryptographic systems used by other governments around the world since the vulnerable smartcards used in the Taiwanese program passed the FIPS 140-2 Level 2 and the Common Criteria standards. The certifications, managed by the National Institute of Standards and Technology (NIST) and its counterparts all over the world, impose a rigid set of requirements on all cryptographic hardware and software used by a raft of government agencies and contractors.

“Trivially broken keys”

The team of scientists uncovered what their paper called a "fatal flaw" in the hardware random number generator (RNG) used to ensure the numbers that form the raw materials of crypto keys aren't based on discernible patterns. Randomness is a crucial ingredient in ensuring adversaries can't break the cryptographic keys underpinning the smartcards issued to Taiwanese citizens.

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Box aims for NSA-resistant cloud security with customers holding the keys

After eight years of existence, file sharing service Box has built a huge user base—claiming 180,000 businesses, including 97 percent of the Fortune 500—by offering cloud storage and collaboration tools with top-notch security and regulatory compliance.

But while Box may be resistant to most criminal hackers, like most cloud storage companies, it must provide the government with customer data when it is forced to. For the vast majority of Box customers, that isn't likely to change. However, the company is developing a system for the most security-conscious customers in which even Box management would not be able to decrypt user data—making it resistant to requests from the National Security Agency.

Box co-founder and CEO Aaron Levie spoke with Ars last week to promote the launch of a new collaboration tool called Box Notes and answered our questions about Box's encryption model.

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