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# vulnerability

guys i just read a vulnerability in the calculator of windows. vulnerability is like this:

*) open calculator

*) type 4 and then take its square

*) then minus two from the result

shocked....

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hackit
Light Poster
31 posts since Sep 2011
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I suppose you are taking course in computer security? Correct me if I am wrong. So what do you want us to help you with?

jingda
Industrious Poster
4,702 posts since Mar 2011
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First of all when you take the square of 4 you get 16. I presume you meant square root. I would imagine that the algorithm used to find the square root results in 2 plus a very very small fraction which is not shown because it is so much smaller than 2. When you subtract 2 from that you are just left with the fractional part which is, at least on my computer, around -8 times 10 to the -39th power which is damn close to zero.

One of the first demonstrations I had on how computers do math was back in 1971 when it was shown that 1/3 + 1/3 + 1/3 was actually slightly less than one according to the computer.

Reverend Jim
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