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matthew_d_green's profile
Matthew Green
Matthew Green
Matthew Green
@matthew_d_green

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Matthew Green

@matthew_d_green

I teach cryptography at Johns Hopkins.

Baltimore, MD
blog.cryptographyengineering.com
Joined January 2010

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    1. Matthew Green‏ @matthew_d_green Apr 7
      • Report Tweet

      Matthew Green Retweeted Colm MacCárthaigh

      I spent the year before Heartbleed visiting important people in DC trying to convince them OpenSSL was a mess, and they should fund it as “critical infrastructure”. They laughed and told me that term referred to dams and power plants.https://twitter.com/colmmacc/status/1114944298246660100?s=21 …

      Matthew Green added,

      Colm MacCárthaigh @colmmacc
      I think right around this minute is just about exactly 5 years since the Heartbleed vulnerability in OpenSSL became public. I remember the day vividly, and if you're interested, allow me to tell you about how the day, and the subsequent months, and years unfolded ... pic.twitter.com/JSZEESmDp8
      Show this thread
      17 replies 321 retweets 782 likes
      Show this thread
    2. Matthew Green‏ @matthew_d_green Apr 7
      • Report Tweet

      My efforts accomplished absolutely nothing, but I learned later than someone in the Obama administration ran it by their superiors. Which made them look smart in the wake of Heartbleed.

      3 replies 13 retweets 95 likes
      Show this thread
    3. Matthew Green‏ @matthew_d_green Apr 7
      • Report Tweet

      The money seemed so tiny compared to the risk companies and government was exposed to. OpenSSL was down to one developer who couldn’t even find resources to go through submitted tickets. https://www.google.com/amp/s/www.nytimes.com/2014/04/10/technology/users-stark-reminder-as-web-grows-it-grows-less-secure.amp.html …pic.twitter.com/fTLbVNKoDy

      2 replies 18 retweets 88 likes
      Show this thread
      Matthew Green‏ @matthew_d_green Apr 7
      • Report Tweet

      Anyway, within a few weeks of Heartbleed the Linux Foundation had established the Core Infrastructure Initiative and poured millions into OpenSSL and other projects. The OpenBSD people tore into the code and livetweeted it at @ValhallaSSL.

      2:51 PM - 7 Apr 2019
      • 15 Retweets
      • 73 Likes
      • EBOLA under the 🌒 i have internet instead of personality Bob Ippolito Despatche Viko OR y Wr ฿ Abraxas Staggered Repeating of Memory Cole
      1 reply 15 retweets 73 likes
        1. New conversation
        2. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          Anyone who tells you ‘an ounce of prevention is worth a pound of cure’ obviously never tried to convince people to invest in prevention. Attacks matter. Security advances one massive, public, messy vulnerability at a time.

          3 replies 55 retweets 154 likes
          Show this thread
        3. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          I guess since we’re talking about OpenSSL and the US government, it’s worth explaining something unique and special about that software that also makes its correct operation particularly important to US national security.

          2 replies 2 retweets 42 likes
          Show this thread
        4. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          Any cryptography software used for sensitive-but-unclassified data protection in USG needs to have FIPS certification. This means an expensive validation that was, for a long time, pretty much inaccessible to open source developers.

          1 reply 1 retweet 44 likes
          Show this thread
        5. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          More critically, even though FIPS validation covers source code, the validation certificate itself did not. You only got to certify the binary. And only for specific architectures. This changed with OpenSSL.

          1 reply 3 retweets 49 likes
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        6. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          Some very bright bureaucratic warriors inside the DoD saw the value of certifying a piece of open source software, and realized this could save the government a ton of money. So they pushed hard and got the first “source code certification” for the OpenSSL FIPS module.

          3 replies 9 retweets 72 likes
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        7. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          To the best of my knowledge, OpenSSL is (still, and definitely for a long time) the only cryptographic product that got this special treatment. You could use the source without recertifying every binary. This was huge for the DoD, so it got used a lot.

          4 replies 11 retweets 71 likes
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        8. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          (The people who run the USG’s Cryptographic Module Validation Program seem to hate this and have been trying to take this exception way for years. As much as I hate FIPS, moving back to proprietary junk seems worse.)

          2 replies 4 retweets 56 likes
          Show this thread
        9. Matthew Green‏ @matthew_d_green Apr 7
          • Report Tweet

          Anyway, the point here is that when Heartbleed came along, it wasn’t just a bug in “some library that people in the government happened to use.” It was a flaw in software that the DoD had made a special exception for, so they could use extensively.

          2 replies 9 retweets 89 likes
          Show this thread
        10. End of conversation

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