Wednesday, May 19, 2010

Encryption by Default

A recent survey was reported as follows:

IDG News Service - Employees at many U.S. government agencies are using unsecure methods, including personal e-mail accounts, to transfer large files, often in violation of agency policy, according to a survey.


Pasted from www.computerworld.com/s/article/9176889/Survey_Gov_t_agencies_use_unsafe_methods_to_transfer_files?taxonomyId=17>

Stephen Northcutt, writing as an editor of SANS Newsbites, observes:

I agree that too many people use insecure means to move data; disagree the root cause is no access to encryption.

A lot of people have access to encryption for email at work and yet consistently send data in the clear. We discuss this in the class I author and teach, and I think we as a community are becoming numb to the dangers we face from the Internet. Pretty Good Privacy (PGP) has been around almost 20 years now. In the early days, when you went to conferences, they had PGP signing parties and almost all the security professionals I interacted with had PGP and a key. Now, almost nobody seems to use it outside of FIRST, AV Research and similar enclaves...(stephen@sans.edu).


In another context this week I was reminded of a lesson I learned a long time ago, "One must make the desired behavior at least marginally easier than the wrong behavior." Almost by definition, "harder to do it right" is too hard.

Twenty years ago we were very concerned that user credentials would be compromised in the network. Today with activity more than a 1000 times what it was twenty years ago, credentials are compromised at the end points, not in the network. The reason is that for data in motion we use encryption. We use SSL. Thanks to Netscape, we use it by default.

When we say our prayers at night we should say, "Thanks for Netscape." Netscape understood that encryption in the World Wide Web was essential, like brakes on a car, not optional. They made it standard, not a separately priced feature. It was included in the function and price of the server. Thinking back on my time at IBM, I have often thought that had IBM invented SSL, they might well have priced it as an option and it would have failed. The way we price things often influences how we think of them and how we use them.

Even though the software is not separately priced, SSL has to be turned on and, at the level of its current default use, it has a significant cost. Nonetheless, we use it pervasively and users have come to expect it. We use it by default. If either party expects it, the other party can hardly avoid it.

Note that the problem addressed by the survey is identified as "file transfer," much of which is not even done in the network but on portable media, on what we used to call the "sneaker net." Much of it is ad hoc, with no standard procedures. Management has not told employees how to transfer data, much less how to do it securely.

The data leaks in dozens of ways. It leaks when users make gratuitous copies and then loses them. It leaks when backup copies fall off the back of the truck. It leaks when hackers compromise servers. It leaks through the user interface of ftp servers and other ways too numerous to enumerate. The user does not even contemplate most of these leakage modes and believes that the ones that he does contemplate are too rare to worry about.

Stephen Northcutt points out that PGP can be used to resist most of these leaks. Even simpler tools like passwords on .doc and .pdf files would resist many of them. PKZip and sftp are powerful tools to help us. However, most of these solutions require user involvement and a high level of user knowledge, not to mention judgment and initiative.

The solution to the problem includes making using encryption on all data easier than not, to make the encryption of data at rest the default, not the exception. It includes providing encryption by default across enterprises. It includes resisting gratuitous copies at the end points, even where the use requires that the data must be in the clear. It includes management direction and automated procedures to implement that direction.

A tall order you say? Suppose I told you that encryption by default is routine, automagic, in many enterprise and government domains and even across domains? True. Just for an example, Lotus Notes protects files and databases at rest, by default, using encryption. Even if one makes a gratuitous copy of the file on one's laptop or thumb-drive, it is encrypted. Notes provides for automatic safe exchange across domains. It provides for automatic key management that is transparent to the users. Obtaining copies of these files and databases in the clear requires both privileges and work. In this environment, it is easier to do it the right way. Indeed, it is so easy that many, not to say most, users do not even know that it is happening.

Though I believe that it is under-sold and under-appreciated, I am not here to sell Lotus Notes. I use it merely as an example of "encryption by default." I believe that encryption by default should be the standard in all government agencies and most private enterprises, and that we have at least one successful model of how to achieve it.

4 comments:

  1. Great post Bill! We will have a follow up in the next Newsbites and it will address the notion of default as defined by Thaler and Sunstein in Nudge. However, you have made the case with the clearest writing and most obvious examples I have seen. What is our next step?

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  2. It's true that encryption should be on by default. This is why I use TrulyMail - because its message and attachment sending system (an email replacement) is encrypted by default. Actually, there is no way to disable encryption. You can enable or disable encryption via email (and it's way easier to use than PGP/GPG).

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  3. I also agree with the notion that all online communications should be encrypted by default. ThreadThat.com provides end-to-end encryption of messages and files along with several other configurable security options like auto logoff, multi-factor authentication, new location detection, etc. This is currently a free service.

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  4. I often use Lotus Notes as having built security in right. However, you can see what happened in market share, especially as more open collaboration became the major demand. The vast, vast majority of data does *not* need to be protected and when protecting the small amount that really is sensitive impedes the sharing of the other information, need to share trumps need to share, outside of high security areas.

    Key management for persistent (vs transport) is a tough problem that needs to be solved to achieve the balance - look at the failure of DRM in the music industry. There are better approaches - like tokenization - that can achieve a better balance of security, complexity and portability.

    Another comment - great to give kudos to Taher Elgamal and SSL for driving logins to have tranport protection, but SSL as implemented lead to one of the worst false senses of security as far as authentication. SSL in no way guarantees the server is who the user thinks it is but Netscape, Microsoft and the rest of the browser CA industry pushed it as "now your transaction is secure!!"

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