You might think that a Lego safe would be easy to open. Maybe just remove a few bricks and you're in. But that's not the case with this thing, the cutting edge of Lego safe technology. The safe weighs 14 pounds and has a motion detecting alarm so it can't be moved without creating a huge ruckus.

Hash functions are the most commonly used cryptographic primitive, and the most poorly understood. You can think of them as fingerprint functions: They take an arbitrary long data stream and return a fixed length, and effectively unique, string. The security comes from the fact that while it's easy to generate the fingerprint from a file, it's infeasible to go the other way and generate a file given a fingerprint.

Originally created to make digital signatures more efficient, hashes are now used to secure the very fundamentals of our information infrastructure: in password logins, secure web connections, encryption key management, virus and malware scanning, and almost every cryptographic protocol in current use. Without cryptographic hash functions, the internet would simply not work. At the same time, there isn't a good theory of hash functions. Unlike encryption algorithms, there are no secret keys involved; this makes it harder to mathematically define exactly what hash functions are.

The National Institute of Standards and Technology, NIST, is holding a competition to replace the SHA family of hash functions. "SHA" stands for "Secure Hash Algorithm." It was developed by the NSA in 1993 to replace the commercial MD4 and MD5 algorithms, and has been updated several times since then. All the SHA algorithms are very similar, and have been increasingly under attack, so NIST wants to replace them.

The competition is important because, unlike other technological standards, committee design — balancing the interests of diverse constituents — isn't conducive to good security. Security is best when it's designed by expert teams and then subjected to public review. And cryptography is best when it's chosen by competition.

In 1997, NIST held a competition for a block cipher to replace DES. Fifteen candidates and three-and-a-half years later, Rijndael became the new Advanced Encryption Standard — AES. NIST is doing the same thing for what it's calling SHA-3 (not, for some unexplained reason, the Advanced Hash Standard or AHS).

The deadline was October 31, and NIST received 64 submissions. This isn't surprising — I predicted 80 — as most of the 15 AES submitters were professors, whose students at the time have become professors themselves, with their own students. (If NIST does a stream cipher competition in another ten years, they should expect about 256 submissions.) These submissions came from academia, from industry, and from hobbyists. CIO magazine recently interviewed one of the submitters, who is 15. Twenty-eight submissions have been made public by the submitters, and six of those have been broken.

NIST is going through all the submissions right now, making sure they are complete and proper. Their goal is to publish all accepted submissions by the end of November, in advance of the First Hash Function Candidate Conference, to be held in Belgium right after the Fast Software Encryption workshop in February.

The group expects to quickly make a first cut of algorithms — hopefully to about a dozen — and give the community a year of cryptanalysis before making a second cut in 2010. After another year of cryptanalysis, NIST will choose a winner in 2011. Expect a final standard by 2012.

My advice for software developers is to let the process run its course. While it's tempting to use the new cool algorithms in your designs, it's far too soon to trust any of them. This process is likely to result in all sorts of new research results in hash function security, and some real cryptanalytic surprises. Give the community a few years to figure out which ones are good and which aren't.

I've previously called this sort of thing a cryptographic demolition derby: The last one left standing wins. But that's only partially true. Certainly all the groups will spend the next few years trying to cryptanalyze each other, but in the end there will be a bunch of unbroken algorithms. NIST will select one based on performance and features.

NIST has stated that the goal of this process is not to choose the best standard but to choose a good standard. I think that's smart; in this process, the best is the enemy of the good. While there's no rush to choose a new standard — the SHA-2 algorithms will remain secure for the foreseeable future — we don't want to analyze the candidates forever.

Personally, I was part of a group of eight cryptographers that submitted Skein to the competition. A decade ago, writing Twofish and participating in the AES process was the most fun I had ever had in cryptography. These next few years promise to be even more fun.

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Bruce Schneier is chief security technology officer of BT. His new book is Schneier on Security.

The latest Microsoft patch MS08-68 is a great example. It is a problem with NTLM authentication where the attacker can force a client to authenticate to him and the credentials, while not exposed in cleartext, can be relayed to another server or brute forced to obtain the cleartext. This is a very classic crypto protocol vulnerability. It’s not the crypto algorithms that are the problem, but the protocol implementation.

Microsoft recently fixed the problem, perhaps due to the availability of exploit code, the availability of an easy to use Metasploit implementation, or perhaps Microsoft’s changed tolerance for vulnerabilities. We can sum it up as a change in the threat space that made it worth fixing. But make no mistake, this is a very old problem.

News reports have been citing Sir Dystic’s SMBrelay tool, which was published in March, 2001, as the first knowledge of this vulnerability. Eric Shultze who worked at MSRC in 2001 just yesterday is quoted as saying, “I have been holding my breath since 2001 for this patch.” Obviously it is a long time coming. But this wasn’t the first publication of the problem. In 2000, one of my collegues on the research team at @stake, Christian Rioux (aka Dildog) published the telnet NTLM authentication vulnerability.

Rioux’s advisory has a great description of the credential relay and cracking weaknesses. I have talked to him and he says he discovered these problems independently, but he didn’t find them first. Dominique Brezinski published exactly these NTLM vulnerabilities in the SMB protocol in 1996 in a paper titled, “A Weakness in CIFS Authentication”. The earliest reference I can find on the paper on the net is here where it is included in another paper published in 1997. Such is the ad-hoc world of independent security research of 12 years ago which still continues today.

It seems ridiculous that a field like security research, which is so important to the running of modern society is so ad-hoc. Shouldn’t we know who discovered a vulnerability? Shouldn’t all researchers and engineers know about it? More importantly if someone implements a tool that takes advantage of a vulnerability shouldn’t they credit the discoverer? Don’t get me wrong. Implementation takes a lot of work and sometimes makes all the difference in makeing people aware of a security problem. After all when I was at the L0pht our slogan was, “Making the theoretical, practical”. I still think researchers should get credit when credit is due.

The security community has gotten better at documentating our research but I still see instances of independent discovery, misplaced credit, and tools giving no credit to researchers. I hate to say it but getting a bit more academic is in order. Credit is the currency of a researcher and placing it well will reward the right people and we will all benefit.

It’s kind of frightening to see how quickly a skilled lock-picker can jimmy a lock and get in. But new technology makes it even simpler — apparently all you need is a good telephoto lens to break in to someone’s house — just wait till they leave their keys out on a table, snap a picture, and take it to an unethical key maker, and wha-la, a perfect replica:

“We built our key duplication software system to show people that their keys are not inherently secret,” said Stefan Savage, the computer science professor from UC San Diego’s Jacobs School of Engineering who led the student-run project. “Perhaps this was once a reasonable assumption, but advances in digital imaging and optics have made it easy to duplicate someone’s keys from a distance without them even noticing.”

Professor Savage presents this work on October 30 at ACM’s Conference on Communications and Computer Security (CCS) 2008, one of the premier academic computer security conferences.

Read the full article here.

One easy, inexpensive way to actually increase your effectiveness in 2009 is to, right now, make a quick review your risk management processes.  As you take a look at how you’re using risk in your organization, I’d ask you to make sure that those processes are providing value for the energy you’re spending.  If they’re not - if you’re not successfully using risk within security and with the other lines of business that you serve - then I’d like to invite you to  come take advantage of RMI’s public training session for 2008, held in Columbus Ohio on December 10-12.  >A brochure is here<.

For three days and $1,995 - you’ll get real answers to many of the commonly voiced frustrations RMI hears concerning risk & risk management.  Answers around measurement, application, communicating risk to other lines of business, heck, basic answers as to what risk is and how to get consistent, defensible values that actually mean something.

Not to mention - Strengthening your Risk Management processes increases your ability to manage risk, which reduces the amount of risk you actually face.

NEW TO THE PUBLIC STUFF!

I’m personally excited because this is the first time that our public training we’ll feature measurement “calibration” exercises and include excel tools to take home and use for quantitative FAIR analysis.  These are benefits we’ve only previously reserved for private client workshops.

I know that FAIR can help you and your organization, but as the sales guys always say, “don’t take my word for it”.  Here’s something we recently received (unsolicited) from the CSO of one of the 10 largest banks in the US, who has had several of his analysts receive this same basic training:

I would like to also add my deep appreciation for what FAIR and RMI has brought to (us) and how we go about the business of risk analysis. We have had some great conversations around risk with the lines of business that have ended very favorably for us.

More information can be found on RMI’s website here:  http://www.riskmanagementinsight.com/12_2008_training.html

Thanks.

Oh and tomorrow, we’ll talk a little bit about quantitative and qualitative risk.