Slashdot Mirror


Zimmermann Enters Debate on Microsoft Encryption

Golygydd Max writes "I didn't see much coverage of the RC4 flaw in Microsoft Office that was uncovered recently by a researcher, Hongjun Wu. Now, PGP creator Phil Zimmermann, dissatisfied with Microsoft's response, has joined in the debate. In an interview with Techworld he castigates Microsoft for their inadequate response: 'The lay user ought to be entitled to assume that the encryption produced by Microsoft is adequate. ... If Microsoft wants to earn the respect of the cryptographic community and the public it must rise to the occasion by producing competent security.' The cynic might ask, 'what respect', but should Microsoft have taken a flaw in some of its most popular programs more seriously?"

20 of 381 comments (clear)

  1. First rule of Microsoft encryption by Anonymous Coward · · Score: 4, Insightful

    Do not use Microsoft encryption.

  2. copyright by oliverthered · · Score: 4, Insightful

    How else are we supposed to get access to all these works in 150 years time (or 50 in some countries) when the copyright expires on them.

    --
    thank God the internet isn't a human right.
    1. Re:copyright by mlush · · Score: 3, Insightful

      >>How else are we supposed to get access to all these works in 150
      >>years time (or 50 in some countries) when the copyright expires on them.
      >Uhhh... Public... Domain?

      If the encryption were unbreakable and the keys lost, it would not be a lot of use

    2. Re:copyright by j0nb0y · · Score: 4, Insightful

      Copyright expiration? Copyrights don't expire. Congress extends them again every 20 years. And they'll keep doing so, forever, since the Supreme Court ruled that it was perfectly okay!

      --
      If you had super powers, would you use them for good, or for awesome?
    3. Re:copyright by Riddlefox · · Score: 3, Insightful
      As has been mentioned, a properly implemented one time pad is completely unbreakable.

      The basic concept is to take a completely random stream of characters (numbers, bits, whatever). You record these random characters to a pad, and distribute this pad to everyone who needs to send and decrypt messages.

      When you want to send a message, you XOR your message with the random characters. The result is a completely random string of characters. To decrypt, you XOR the encrypted message with the same random characters that were used to encrypt the message.

      Since you are combining a message with random data, it's unbreakable.

      For instance, you get a string of random characters and try to decrypt it:
      #*YRHOIHSDF&VP
      What does it decrypt to?
      ATTACK AT DAWN
      SURRENDER NOW.
      GO FOR THE GUN
      I LOVE SWEETS!
      PAY ME $10,000
      CMDRTACO SUCKS
      NO HE DOESN'T!

      Which message is it? You can't tell, because you can't tell which random letters I used to transform my message.

      However, you can't reuse any of the pads, else the message is crackable. You must have a very high quality source of random characters. You must securely distribute the one time pad to everyone who could need to communicate. You must ensure everyone stays synchronized. There's a bunch of problems with one-time pads, which is why it's not more commonly used.

    4. Re:copyright by arose · · Score: 3, Insightful
      What is the real difference between copyrights (specific expressions of an idea) and physical property?
      The physical part.
      --
      Analogies don't equal equalities, they are merely somewhat analogous.
  3. Re:MS Encryption is a joke by gUmbi · · Score: 4, Insightful

    One of its highlights is that the first administrator account set up in a domain is designated an "Encrypted Data Recovery Agent". What does this mean?

    For corporations (the target market for EFS), it means that if someone is fired, quits, dies, etc. then their data is not lost foreever.

  4. Re:MS Encryption is a joke by danheskett · · Score: 4, Insightful

    MS encryption should be better, but what you describe is not a flaw.

    In a corporate setting it should not be permissible for an employee to conceal data from the owner of the data and machines. The owner of machine - aka the corporation - should have final say over what is encrypted or not.

    Imagine what could be done if there was no way for a high-level sysadmin to decrypt user files. Imagine the damage that could be done.

    AI spiteful (ex)-employee could easily encrypt and forever destroy sensitive data that is irreplaceable.

    Not only that, but it is entirely possible that the user could accidentally render the data unencryptable. That'd be bad.

    EFS is not for a typical user to permanently encrypt data that can never be revealed. It is primarily designed so that sensitive data on corporate laptops can be stored in a way that if it is stolen it cannot be decrypted. This purpose is well served by EFS.

    There are many excellent critiques of MS's security and data protection capabilities. There is no need to overreach and bash things that do actually work as intended.

  5. GPG/PGP by digitalchinky · · Score: 4, Insightful

    You could always just dump their encryption and use PGP/GPG in its place.

  6. Why it is "low priority" by Anonymous Coward · · Score: 5, Insightful

    MS considers it a low priority because there is no tool that currently is known to be available that can leverage the theoretical issues brought up in the paper. I agree with them. An issue is "high priority" when there is a tool that can be used by an end user now as an exploit. That is how you prioritize things in real life.

    1. Re:Why it is "low priority" by quigonn · · Score: 4, Insightful

      That is how you prioritize things in real life.

      This "there is no program to exploit it, so this security issue is not important"-type of attitude is extremely dangerous. The slogan is to act, not to react, especially with security issues. And Microsoft actually should have learned from their part of history...

      --
      A monkey is doing the real work for me.
  7. Who uses word to protect anything? by Vellmont · · Score: 3, Insightful

    While Microsoft should probbably fess up and fix the problem, is this really such a big deal? Who uses Microsoft word encryption, and for what? It still sounds like you'd require multiple versions of the same document. That means either access to the data store itself where the document was being edited, or the user has passed around multiple versions to others.

    I guess what it comes down to is expectations of security. It should be obvious to not use word to protect national secrets. Secret love letters to your mistress are still probbably safe from your wife though (unless she happens to be a crypto-expert). In that case it's probbably easier to just use a keylogger, or install a trojan horse.

    --
    AccountKiller
  8. Indeed: what respect? by FridayBob · · Score: 4, Insightful

    Their programmers might care, but M$ itself isn't interested in respect from the cryptographic community, because it's something that doesn't matter to their stockholders; it's too obscure for them to care about. M$ only responds to this kind of thing once the news gets out and the public begins to perceive it as a problem. Security through obscurity, remember? Basically, M$ are only in it for the money; a statement that explains their entire track record.

  9. Re:MS Encryption is a joke by 0123456 · · Score: 4, Insightful

    "Imagine the damage that could be done."

    Such as, exactly?

    "AI spiteful (ex)-employee could easily encrypt and forever destroy sensitive data that is irreplaceable."

    Or they could just del *.*. Or format c:. Or burn down the building.

    This whole 'spiteful employee' argument is nonsense. The only reasons to have a 'key recovery agent' are to recover password for clueless employees and to spy on slightly more clued employees.

  10. Users don't want strong MS Office encryption by gfecyk · · Score: 4, Insightful

    Least of all your US government. The NSA makes a bulletproof distribution of Linux, and other US government offices shun it in favour of Windows.

    Sun Microsystems released Star Office, and a bunch of open source wonks built OpenOffice, with better track records. Yet US government offices shun them in favour of Microsoft Office.

    I'm not sure why they do, especially an omniscent body like the US government who knows these things exist. It must be because they don't want to use them.

    And every day users? Well, users could have taken e-mail content security into their own hands over a decade ago when PGP was out, or eight years ago when PGP for the Exchange client came out. But NO, they didn't want to use it. They could have used S/MIME which was slightly easier to use, but NO, they didn't want to use it.

    Users don't care enough to demand strong encryption in their applications. And Microsoft is in business to make money. They aren't going to waste time making a product that no one will buy. And YOU, slashdotters, aren't going to convince users to buy an alternative through fear, uncertainty and doubt.

    --
    Use Evolution instead of Outlook? Bewa
  11. Re:Encryption easily broken by Vellmont · · Score: 4, Insightful


    1) That password you give your administrator account on your system can be hacked off in under 5 minutes with the Emergency Boot CD EBCD . So much for encryption.

    That doesn't have anything to do with encryption. Anytime you have physical access to a computer all bets are off as far as security. You can do the exact same thing in linux, and most of the time you don't even need a CD. Just add a 1 to the kernel boot options and boot into single user mode. No password required, immediate root access. Sure, you can put a password on changing those bootloader options, but just slap in a linux emergency boot CD, and suddenly you have root access to all files.

    Linux encrypted filesystems I know almost nothing about, but I've also never seen a distribution that supports it out of the box. There's probbably one out their, but it's not a mainstream linux feature.

    --
    AccountKiller
  12. What's left to say? by HarveyBirdman · · Score: 3, Insightful
    I didn't see much coverage of the RC4 flaw in Microsoft Office that was uncovered recently...

    Maybe everyone is just burned out and tired of the topic. We all know that the state of PCs in the world today is a vast, pathetic farce of biblical proportions thanks to MS. What's left to say about it? Windows is a shitpile, but people keep gobbling it up. Just like they gobble up all the other sludge in our culture. Nothing unusual to be seen here. Move along.

    --
    --- Ban humanity.
  13. Re:MS Encryption is a joke by rikkards · · Score: 3, Insightful

    Maybe at home but corporate computers are corporate property. There is not expected level of privacy on said property. If you don't want someone at work from looking at your private stuff then don't keep it on business machines.

  14. Re:MS Encryption is a joke by Proteus · · Score: 5, Insightful

    While I agree that the 'spiteful employee' arguement is largely bunk, the 'employee who quit, got fired, or otherwise left unexpectedly' arguement is not.

    e.g. I am a sysadmin, and I store all the incident reports on a Win2k3 EFS box, encrypted to my key. These incident reports are important to whomever is doing my job -- no one needs to see them unless I leave unexpectedly. If I get trampled by a herd of malicious gnus on the way to work, the top-level admins will need access to my data, as will whoever replaces me.

    There are two solutions to that -- share my key or use the EFS recoverable key system. Guess which I'd rather do?

    --
    We may not imagine how our lives could be more frustrating and complex—but Congress can. – Cullen Hightower
  15. It's a big, stupid, ugly bug by big-magic · · Score: 3, Insightful

    There is a lot of speculation here that Microsoft put in this encryption bug on purpose. That's giving them too much credit on this one. I just read the paper about the weakness. They are essentially reusing the same keystream more than once. That's an amateur level bug that is discussed in any crypto book that talks about stream ciphers. Look in the book Applied Crytography by Bruce Schneier in the section on cryptographic modes. He talks about this directly. This is not a minor threat. It's a gaping hole since a simple XOR of two versions of the document gives you a lot of information.

    The bigger question is why Microsoft used a stream cipher for this. As Zimmerman mentions, they are more difficult to use correctly. Although some weakness in RC4 have been found, it is still possible to use it in a strong manner. You just have to be careful. It would have been better to use a good block cipher (AES, Triple DES, blowfish, etc) and a simple mode like CBC. It's easy to code and still plenty strong if you reuse the same initialization vector. Even better would have been a newer mode like CCM.