ACCESS CONTROL ISSUES 3 - CONTENT PROVIDER VULNERABILITY
- Layout for this exercise:
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- Connecting from Santoku to Nexus 5 with ADB:
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- Launching the application:
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- Let's see how the challenge 11 works. Clicking the tab:
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- The user is prompted to create a PIN to protect private information stored on the application:
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- Using the newly created PIN, access to some private notes is available:
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- The goal of this challenge is to bypass the access control provided by the PIN, being able to read the private notes from outside the application.
- A content provider manages access to a central repository of data. A provider is part of an Android application, which often provides its own UI for working with the data.
- However, a content provider is primarily intended to be used by other applications, which accesses the provider using a provider client object. In other words, content providers are the standard interface that connects data in one process with code running in another process.
- Checking the source code for the activity AccessControl3Activity.java:
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- Also, the source code of AccessControl3NotesActivity.java:
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- In the same way, checking the AndroidManifest.xml, the content provider jakhar.aseem.diva.provider.notesprovider is detected.
- One of its parameters is androd:exported="true", what makes it vulnerable to be accessed without permission. In order to make it secure, it should be put to either "false" or added a permission to access it:
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- Using the finduri option by Drozer, the content provider is found:
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- Running the query option by Drozer, the notes are available from Santoku, outside of the application:
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- Also, adb shell content query can be used to access the notes:
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