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compare with unknown value malware disassembly ?


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cmp dword_4298B8, eax
jnz short loc_xxxx

dword_4298B8 is initialized as "dd ? "

then how to compare with eax?
dword_4298B8 --->  dd ?


Can you give me an example of array and accessing it and allocating it in ASM when i do reverse egnineering! 


mov WORD PTR [ebx], 2


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dword is initialized as dd ? which means its uninitialised memory, filled at runtime by something

cmp dword ptr [0x12345678], eax would be such a comparison

DWORD ptr points to a dword, so the comparison is dword

WORD ptr points to a word, so the comparison is word

BYTE ptr points to a byte, so the comparison is a byte

theres others like qword ptr, tbyte ptr and so on... this is pretty much asm 101 though, so i'd suggest you go read some asm books

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