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Amazon Is Downloading Apps From Google Play and Inspecting Them

blog.rajbala.com

11–20 of 113 posts

Re: Amazon Is Downloading Apps From Google Play and Inspecting Them

#15

I wonder how they would identify a string that appears to be an API secret, and queries their database for it. For every plausible string in every app? I guess they decompile it and find string literals of the correct length?

You can build a trie of all the AWS keys and then for each Android binary, traverse each series of bytes until it either terminates at a leaf node or fails to continue. If it fails, you start over again on the next byte. Or in order words, the trie allows you to easily test if a given byte is the start of an AWS key, and so then you just check every possible offset. Believe the run time will only be O(n*k) where n is the size of the binary and k is the size of the AWS key, plus enough memory to store the trie which is probably relatively small; less than 1m AWS accounts?

Re: Amazon Is Downloading Apps From Google Play and Inspecting Them

#17
Conjecture, and I guess you're welcome? My guess is if you embedded your Google cloud credentials in your app and it was compromised Google would be happy to bill you, terminate your account, or otherwise provide zero latitude as a customer. At least they dropped their prices, right?

Re: Amazon Is Downloading Apps From Google Play and Inspecting Them

#18
post #14

Couldn't they just look at the user agent and know that the hit to their API is coming from an Android device rather than a server?

http://developer.android.com/reference/java/net/HttpURLConne... might not have a default User-Agent header that identifies android

Re: Amazon Is Downloading Apps From Google Play and Inspecting Them

#20

This is probably a good thing and also automated.

It could have raised alarms and then personally investigated. You Could monitor distribution of AWS connections per client. You could easily determine that accessing the same account from many android devices is probably result of poor security practices.
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