david wong

Hey! I'm David, cofounder of zkSecurity and the author of the Real-World Cryptography book. I was previously a crypto architect at O(1) Labs (working on the Mina cryptocurrency), before that I was the security lead for Diem (formerly Libra) at Novi (Facebook), and a security consultant for the Cryptography Services of NCC Group. This is my blog about cryptography and security and other related topics that I find interesting.

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Bullrun posted November 2013

Bullrun or BULLRUN is a clandestine, highly classified decryption program run by the United States National Security Agency (NSA). The British signals intelligence agency Government Communications Headquarters (GCHQ) has a similar program codenamed Edgehill. According to the NSA's BULLRUN Classification Guide, which was published by The Guardian, BULLRUN is not a Sensitive Compartmented Information (SCI) control system or compartment, but the codeword has to be shown in the classification line, after all other classification and dissemination markings. Information about the program's existence was leaked in 2013 by Edward Snowden.

from https://en.wikipedia.org/wiki/Bullrun_%28decryption_program%29" target="_blank">wikipedia.

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SecureDrop posted October 2013

SecureDrop is an open-source whistleblower support system, originally written by Aaron Swartz and now run by the Freedom of the Press Foundation. The first instance of this system was named StrongBox and is being run by the New Yorker. To further add to the naming confusion, Aaron Swartz called the system DeadDrop when he wrote the code.
from Schneier's blog

You can find http://deaddrop.github.io/" target="_blank">the website here and if you have something important to submit and do not want to go through Wikileaks, I think this is the best alternative.

The security audit was done by Schneier himself, who is pretty popular in the cryptography community, the work was started by Aaron Swartz who is also extremly popular, especially since his suicide last year.

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New effort to fully audit TrueCrypt raises $16,000+ in a few short weeks posted October 2013

I just learned that TrueCrypt, the multi-OS solution to encrypt your personal data in a "very easy way" is coded and maintained by ... no one knows. Like bitcoin, the main creators are anonymous. http://www.truecrypt.org/downloads2" target="_blank">The source code is available here but no info about the coders can be found.

It seems like folks are getting a bit worried as TrueCrypt is wildly used, and money is being raised to conduct a security audit on them. http://arstechnica.com/security/2013/10/new-effort-to-fully-audit-truecrypt-raises-over-16000-in-a-few-short-weeks/" target="_blank">More info here.

Now I'm wondering, why is it that those huge cryptographic applications, that are polished and well maintained, are created by anonymous persons? Do they fear they would get pressure from governments? Mafia? Who knows...

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Baidu now accepts bitcoins! posted October 2013

It's official, http://www.baidu.com" target="_blank">Baidu, the chinese google, now accepts bitcoins.

"As a cutting-edge IT guy and a professional webmaster, what else can showcase our difference? The answer is that we have Bitcoin! Bitcoin, as a new electronic and digital currency, is being accepted internationally. It's also used in daily lives. You can use Bitcoin buy a cup of coffee, or easily convert it to cash. But in China, Bitcoin is still a fairly new thing. Today, we have a good news: from today, we are starting to officially accept Bitcoin as a payment method. You can use Bitcoin to buy all Baidu Jiasule services. Baidu Jiasule as an innovator in the Internet industry, is now the first cloud service provider to accept Bitcoin and give everyone a better payment method and experience."

Read more on https://bitcointalk.org/index.php?topic=310962.0" target="_blank">the bitcointalk about it.

The bitcoin who has been remarkably stable these past weeks, even after the silk road shutdown, has increased a bit more since the announcement.

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Silk Road caught, Tor compromised? posted October 2013

Silk Road and its owner have just http://www.reuters.com/article/2013/10/02/crime-silkroad-raid-idUSL1N0HS12C20131002" target="_blank">got caught by the FBI. If you didn't know, silk road (an illegal drug market) was hosted on the Tor network as an onion website, which was suppose to grant him total anonymity. Apparently the catch was made from a stupid human mistake :

1) Located the first reference to "silk road" on the internet. You can find this yourself on Google: "silk road" site:shroomery.org Date range: Jan 1,2011 - Jan 31,2011 * 2) The same username, "altoid", showed up on a bitcointalk days later. 3) Later in 2011 "altoid" made a post on bitcointalk with his email address, containing his real name, in it: https://bitcointalk.org/index.php?topic=47811.msg568744#msg5... If you search the name on Google it doesn't show up, but if you look at the user's page you can see it in his posts.

But some are skeptical, and many seems to think it could have been http://www.theguardian.com/world/2013/oct/04/tor-attacks-nsa-users-online-anonymity" target="_blank">the NSA getting into the Tor Network. What do you think?

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RSA-210 has been factored! posted October 2013

The https://en.wikipedia.org/wiki/RSA_Factoring_Challenge" target="_blank">RSA Factoring Challenge has had one of its entry factored : RSA-210. More info here.

The RSA Factoring Challenge was a challenge put forward by RSA Laboratories on March 18, 1991 to encourage research into computational number theory and the practical difficulty of factoring large integers and cracking RSA keys used in cryptography. They published a list of semiprimes (numbers with exactly two prime factors) known as the RSA numbers, with a cash prize for the successful factorization of some of them. The smallest of them, a 100 decimal digit number called RSA-100 was factored by April 1, 1991, but many of the bigger numbers have still not been factored and are expected to remain unfactored for quite some time.

The challenge is no longer active, this means no money for this brave Ryan P. And this doesn't mean RSA is less secure so no worries :)

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