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Re: [hybi] Why redirects are a bad for the security of WebSockets (was Re: Clarify wheter HTTP responses other than 101 are valid)

Adam Barth <ietf@adambarth.com> Mon, 28 March 2011 23:33 UTC

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From: Adam Barth <ietf@adambarth.com>
Date: Mon, 28 Mar 2011 16:34:34 -0700
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To: Iñaki Baz Castillo <ibc@aliax.net>
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Cc: hybi@ietf.org, Patrick McManus <pmcmanus@mozilla.com>
Subject: Re: [hybi] Why redirects are a bad for the security of WebSockets (was Re: Clarify wheter HTTP responses other than 101 are valid)
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On Mon, Mar 28, 2011 at 4:22 PM, Iñaki Baz Castillo <ibc@aliax.net> wrote:
> 2011/3/28 Adam Barth <ietf@adambarth.com>:
>> Reading this code, it's quite natural to assume that sending and
>> receiving information on socket will actually communicate with
>> example.com.  For example, I might send confidential information to
>> example.com or rely upon the integrity of information received from
>> example.com.  However, if example.com has has an open redirector (as
>> is extremely common on the Internet), this assumption is incorrect and
>> leads to vulnerabilities.
>
> Let me a question: if you would trust the connection with example.com,
> why shouldn't you trust it in case it redirects you to other place?

As stated above, we're assuming example.com has an open redirector.

Adam

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