if (ip.proto == TCP) {    
    if (tcp.src == 2404 || tcp.dst == 2404) {    
        if (DATA.data+6 == 0x64 && DATA.data+8 == 0x07) {  
            msg(" pos activation - drop \n");                                         

We're able to successfully drop and inject packet using the ettercap filter above.

fake_pkt file content is "\x68\x04\x07\x00\x00\x00".

The injected content size is 24 characters and the injected packet contents are "\x68\x04\x07\x00\x00\x00", as text.

But our goal is to send a binary packet (68,04,07,00,00,00) of the size equal to 6 bytes.

May I know how to write hex values into the fake_pkt file to achieve our goal?


inject() inserts the contents of a file as is. You need to create a binary file, 6 bytes long, and inject that. There are plenty ways to do that, one of the simplest is to use Python:

python3 -c "
with open('./fake_pkt', 'wb') as pkt:
    pkt.write(bytearray([0x68, 0x4, 0x7, 0x0, 0x0, 0x0]))"

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.