Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.

This is the legacy version of twitter.com. We will be shutting it down on June 1, 2020. Please switch to a supported browser, or disable the extension which masks your browser. You can see a list of supported browsers in our Help Center.

  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
taviso's profile
Tavis Ormandy
Tavis Ormandy
Tavis Ormandy
Verified account
@taviso

Tweets

Tavis OrmandyVerified account

@taviso

Vulnerability researcher at Google. This is a personal stream, opinions expressed are mine.

California
taviso.decsystem.org
Joined April 2008

Tweets

  • © 2020 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Imprint
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. Tavis Ormandy‏Verified account @taviso May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @halvarflake @rene_mobile and

      No, the argument is about using reproducible builds to reduce the need to trust the vendor. I'm saying it doesn't do that at all, it can be a poor way to check if a *trusted* vendor has had their build infrastructure is compromised.. but that's about it 🤷🏻‍♂️

      2 replies 0 retweets 2 likes
    2. Tavis Ormandy‏Verified account @taviso May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @halvarflake and

      I think we all agree having source code is beneficial, and we all agree that providing build seeds and source to someone could let them check if your build infra was compromised (but says nothing about whether you're malicious or not).

      2 replies 0 retweets 2 likes
    3. Tavis Ormandy‏Verified account @taviso May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @halvarflake and

      I think the key point is: Reproducible builds do not prevent backdoors.

      1 reply 0 retweets 7 likes
    4. Markus Vervier‏ @marver May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @halvarflake and

      I had some discussions about reproducible builds for security of Linux distros in recent times. It helps to ask where the compiler is actually bootstrapped from + Ken Thompson..

      1 reply 0 retweets 1 like
    5. Arrigo Triulzi‏ @cynicalsecurity May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marver @taviso and

      … and on which microcode the processor compiled it was running ¯\_(ツ)_/¯

      1 reply 0 retweets 3 likes
    6. Markus Vervier‏ @marver May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @cynicalsecurity @taviso and

      Also that..yet hardware (or let's call it low-level) backdoors are not even the scenario..I think reproducible builds will not even help against higher level backdoors. Starting with BUGdoors.

      1 reply 0 retweets 2 likes
    7. Markus Vervier‏ @marver May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marver @cynicalsecurity and

      Reproducible builds belong to this class of mitigations that prevent exactly one scenario (malicious binary distributed together with non-malicious source, i.e. backdoored binray). I'm not saying they're totally useless, but certainly they are not holding up to what's advertised.

      1 reply 0 retweets 1 like
    8. Markus Vervier‏ @marver May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marver @cynicalsecurity and

      Upside: once we have them, reseraching backdoors gets interesting again...I wonder if you can create some sublte BUGdoors with shared libraries...or maybe there's some polyglott LLVM IR...interesting times :-)

      1 reply 0 retweets 0 likes
    9. Arrigo Triulzi‏ @cynicalsecurity May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marver @taviso and

      There is nothing wrong in going "full Gentoo" as long as you understand the meaning of it all: compiling a trusted compiler to then build a trusted system is all very well as long as you can verify (at least) that first step… "Reflections on trusting trust" all the time.

      2 replies 1 retweet 2 likes
    10. Tavis Ormandy‏Verified account @taviso May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @cynicalsecurity @marver and

      True, but the discussion was more about what does verifying the build buy you? If the person who gave you the source code was malicious, then they can embed a bugdoor and there is zero penalty to them if they're caught. You *have* to trust them.

      2 replies 0 retweets 1 like
      Tavis Ormandy‏Verified account @taviso May 23
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @cynicalsecurity and

      Even worse, if you catch catch someone trying to embed a bugdoor, they might tell you to keep quiet for a few months... or *you* might get threatened or called "irresponsible" 😂Bugdoors are just perfect, I will never understand why everyone is so fixated on backdoors.

      1:44 PM - 23 May 2020
      • 3 Retweets
      • 6 Likes
      • Jack Lloyd Finn Markus Vervier Account Overdrawn Arrigo Triulzi
      3 replies 3 retweets 6 likes
        1. New conversation
        2. Arrigo Triulzi‏ @cynicalsecurity May 23
          • Report Tweet
          • Report NetzDG Violation
          Replying to @taviso @marver and

          Dunno, why do you insist in having showers and then breaking AV software? :p Bugdoors are very elegant under many aspects.

          1 reply 0 retweets 2 likes
        3. Markus Vervier‏ @marver May 23
          • Report Tweet
          • Report NetzDG Violation
          Replying to @cynicalsecurity @taviso and

          Just imagine a piece of code that just causes a vuln when compiled for some specific CPU revision...e.g. exploiting one of these floating point bugs Intel always has now and then....

          3 replies 0 retweets 1 like
        4. 1 more reply
        1. New conversation
        2. Markus Vervier‏ @marver May 23
          • Report Tweet
          • Report NetzDG Violation
          Replying to @taviso @cynicalsecurity and

          I just imagine you reporting a bugdoor to somebody evil and having to stick to the 90 days disclosure deadline... sorry users, it would be irresponsible to publish this right now! 😂

          1 reply 0 retweets 2 likes
        3. Arrigo Triulzi‏ @cynicalsecurity May 23
          • Report Tweet
          • Report NetzDG Violation
          Replying to @marver @taviso and

          "because (large) companies are never ever under the influence of nations"

          0 replies 0 retweets 1 like
        4. End of conversation
        1. Stef‏ @Stef_van_Dop May 23
          • Report Tweet
          • Report NetzDG Violation
          Replying to @taviso @cynicalsecurity and

          Less spy movie appeal i guess :)

          0 replies 0 retweets 0 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2020 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Imprint
        • Cookies
        • Ads info