I would like program an oracle service which I would like to charge a fee for. Therefore, I would store the data of interest as a private variable in my oracle contract. This private variable should only be accessed via a function which requires a minimum value payed by the calling contract.
I wonder, is my private variable really protected against phishing by other contracts? More specifically, is it possible to read a private variable of a different contract by any means? Obviously, it does not work with the standard solidity code but is it possible using assembly?