Bite-code
60 points Medium

I dunno what bytecode is. Could you tell me what input of 'checkNum' will return true? The flag is just a 32-bit signed integer as a decimal (nothing else.) https://mega.nz/#!qfATFaKR!zaTNExq3Bm1MjJnePjTGQyvnvLX_xZxhbGaMv_ypaxo

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Reverse Engineering ยท thekidofarcrania
705 solves
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inuvik

6 days ago

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Great challenge, that was my first contact with java bytecode so learnt sth

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zielony12

11 months ago

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Pro tip: use C for brute forcing.

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mmk101

2 years ago

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https://en.wikipedia.org/wiki/List_of_Java_bytecode_instructions

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cezeitar

2 years ago

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yusuf0x

2 years ago

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this is a useful link https://en.wikipedia.org/wiki/List_of_Java_bytecode_instructions

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RutraSan

3 years ago

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Had problems with the program that should have calcualted the flag, then switched from Python to C and everything was ok lmao Feel sorry for those who solve with bruteforcing, I am sure that was not the idea, and understanding how to reverse the equation is fun

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Thorse

1 year ago

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Thank you

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justapwnermaybe

3 years ago

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Emiluren

3 years ago

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Mike_Root

3 years ago

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Very cool. Had to spend a lot of time to understand the java code. Gave up and came back at least twice.

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