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 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @RichFelker @SwiftOnSecurity and

      Rich... come on 🤣

      1 reply 0 retweets 1 like
    2. Matthew Hardeman‏ @mdhardeman 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @RichFelker and

      I concur. Would that real privacy could exist even at work, but that's not life and there are employers who only reluctantly deploy this stuff because they're legally required to. I'm not debating validity of corporate MITM. It's valid and needed.

      1 reply 0 retweets 0 likes
    3. Matthew Hardeman‏ @mdhardeman 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @mdhardeman @taviso and

      Where I think there's room for improvement is that I don't believe there's any good reason for any of Chrome's product decisions to be based on not inconveniencing that segment.

      1 reply 0 retweets 1 like
    4. Tavis Ormandy‏Verified account @taviso 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @mdhardeman @RichFelker and

      Where did you get this "invoncenicing" from? The problem is we don't want them in our address space, because they will get it wrong and make things worse and less discoverable for users! Explain how a user finds out if chrome.exe is being hooked, is that easier or harder than CA?

      1 reply 0 retweets 0 likes
    5. Tavis Ormandy‏Verified account @taviso 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @mdhardeman and

      Do you think you can safely inject a DLL and hook chrome? I don't think you can, it's really hard. I think you probably can set up a corporate CA. I don't think you should, but if I have to pick one - I pick the latter.

      1 reply 0 retweets 0 likes
    6. Matthew Hardeman‏ @mdhardeman 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @RichFelker and

      Concur. But where I think this hypothetical hook comes into play is when Bluecoat customers can't log in using a WebAuthn token because of the MITM + a token binding requirement for the auth from the server side.

      1 reply 0 retweets 0 likes
    7. Matthew Hardeman‏ @mdhardeman 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @mdhardeman @taviso and

      My belief is that this shouldn't discourage token binding or similar anti MITM techniques which offer realistic security benefit just because they may make the MITM vendors desperate. Just ensure that forking their own browser is easier for them than patching yours.

      2 replies 0 retweets 0 likes
    8. Tavis Ormandy‏Verified account @taviso 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @mdhardeman @RichFelker and

      That's the problem, Token Binding *doesn't* offer any security benefit *and* we think it will force people to start hooking. If there was a huge security win here, who wouldn't take that deal?

      1 reply 0 retweets 1 like
    9. Matthew Hardeman‏ @mdhardeman 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @RichFelker and

      U2F can utilize token binding to ensure that the two TLS endpoints speaking to each other are the parties to the authentication process. Presently, this is a gap in U2F coverage and a party today could actually MITM a U2F authentication.

      1 reply 0 retweets 0 likes
    10. Tavis Ormandy‏Verified account @taviso 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @mdhardeman @RichFelker and

      Arghh! No, it can't. Token Binding *can* (depending on implementation) make sure that you're talking to the machine you're think you are, but it can't promise that machine isn't compromised. There is no attack that TB prevents, it just changes how you exploit it.

      1 reply 0 retweets 0 likes
      Tavis Ormandy‏Verified account @taviso 22 Aug 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @mdhardeman and

      Describe how U2F MITM today would work without Administrator access or compromised endpoint. Now either of those things is enough to defeat Token Binding, so what did you solve? Nothing.

      2:33 PM - 22 Aug 2018
      1 reply 0 retweets 0 likes
        1. New conversation
        2. Matthew Hardeman‏ @mdhardeman 22 Aug 2018
          • Report Tweet
          • Report NetzDG Violation
          Replying to @taviso @RichFelker and

          Admin access to install corporate CA for the target origin. U2F MITM would work. If, however, a server-side is able to insist on token binding, a whole extra level of serious patching would be required to MITM. Shifts more control of MITM acceptability policy to server side.

          1 reply 0 retweets 0 likes
        3. Tavis Ormandy‏Verified account @taviso 22 Aug 2018
          • Report Tweet
          • Report NetzDG Violation
          Replying to @mdhardeman @RichFelker and

          So we're in agreement that there is no attack that Token Binding prevents? I get that you (correctly) say if we ship DRM & Token Binding, MITM will be harder (but not impossible). Still can do key logging, screen sharing, remote desktop and type in console, etc.

          1 reply 0 retweets 0 likes
        4. 6 more replies

      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