[OAUTH-WG] Public client cloning

Masakazu OHTSUKA <o.masakazu@gmail.com> Tue, 10 September 2019 15:13 UTC

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From: Masakazu OHTSUKA <o.masakazu@gmail.com>
Date: Tue, 10 Sep 2019 18:13:15 +0300
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Subject: [OAUTH-WG] Public client cloning
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Hi,

I've read rfc8252 and have questions about native apps, that I couldn't
find answers on Internet.

Imagine an attacker doing:
1. original app and authorization server conforms to rfc8252 4.1.
Authorization Flow for Native Apps Using the Browser
2. clone the original app, name it malicious app and install on the target
phone
3. remove the original app from the target phone
4. use the malicious app and authorize, OS will invoke malicious app using
custom URL scheme
5. now malicious app has access to the access token

How should we think about this?
What am I missing?