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by paulsecwhatt 4131 days ago
TL;DR - the author claims to have hacked their encryption by reading the messages in phone memory.

I don't understand how this is a valid exploit/vulnerability? How would any device, Android or not, render the actual picture of the message on the GPU without having the unencrypted string in memory? It's not possible. If you have local memory/code execution, you will ALWAYS have access to the messages any client application is rendering/using.
1 comments
itistoday2 4131 days ago
Yeah, the memory thing didn't impress me. More concerning though is that apparently messages are stored in plain text on disk in that cache4.db file. It's not clear to me whether they are deleted when the app quits or what.
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bdotdub 4131 days ago
Yeah, I'm feeling like the quotes should be around "Hacked", and not "Encryption"
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ch0wn 4131 days ago
The files under `/data/data/[pkgname]` are only readable by the corresponding application. Encrypting them wouldn't add any security as the key for that cache would also be stored on the device.
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itistoday2 4131 days ago
> Encrypting them wouldn't add any security as the key for that cache would also be stored on the device.

That's why you use a user-derived key (i.e. based on the pin or w/e).

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