diff --git a/python-ofensivo/11_chat_cifrado_E2E/client.py b/python-ofensivo/11_chat_cifrado_E2E/client.py
new file mode 100644
index 0000000..b420417
--- /dev/null
+++ b/python-ofensivo/11_chat_cifrado_E2E/client.py
@@ -0,0 +1,130 @@
+#!/usr/bin/env python3
+"""
+CLIENTE DE CHAT CIFRADO E2E
+"""
+
+
+import socket as s
+import threading as th
+from tkinter import *
+from tkinter.scrolledtext import ScrolledText
+
+
+def send_message(client_socket, username, text_widget, entry_widget):
+
+    local_address = client_socket.getsockname()
+    ip_address, port = local_address
+
+    message = entry_widget.get()
+    client_socket.sendall(
+        f'{username} ({ip_address}:{port}): {message}\n'.encode())
+
+    entry_widget.delete(0, END)
+    text_widget.configure(state='normal')
+    text_widget.insert(END, f'{username} ({ip_address}:{port}): {message}\n')
+    text_widget.configure(state='disabled')
+
+
+def receive_message(client_socket, text_widget):
+
+    while True:
+
+        try:
+            message = client_socket.recv(1024).decode()
+
+            if not message:
+                break
+
+            text_widget.configure(state='normal')
+            text_widget.insert(END, message)
+            text_widget.configure(state='disabled')
+
+        except:
+            break
+
+
+def list_users_request(client_socket):
+
+    client_socket.sendall("!usuarios".encode())
+
+
+def exit_request(client_socket, username, window):
+
+    client_socket.sendall(
+        f"\n[!] El usuario {username} ha abandonado el chat\n".encode()
+    )
+    client_socket.close()
+
+    window.quit()
+    window.destroy()
+
+
+def client_program():
+
+    host = 'localhost'
+    port = 1234
+
+    client_socket = s.socket(s.AF_INET, s.SOCK_STREAM)
+    client_socket.connect((host, port))
+
+    username = input("\n[+] Introduce tu usuario: ")
+
+    if not username:
+        username = "Anonymus"
+
+    client_socket.sendall(username.encode())
+
+    window = Tk()
+    window.title(f'Chat cifrado E2E - {username}')
+    # window.geometry('500x700')
+    # window.iconbitmap("oveja-negra.ico")
+    # window.iconphoto(False, PhotoImage(file="oveja-negra.png"))
+
+    text_widget = ScrolledText(window, state='disabled')
+    text_widget.pack(padx=5, pady=5)
+
+    frame_widget = Frame(window)
+    frame_widget.pack(fill=BOTH, expand=True, padx=5, pady=5)
+
+    entry_widget = Entry(frame_widget, font=('Arial', 12))
+    entry_widget.bind(
+        "<Return>",
+        lambda _: send_message(
+            client_socket, username,
+            text_widget, entry_widget
+        )
+    )
+    entry_widget.pack(side=LEFT, fill=BOTH, expand=True, padx=5, pady=5)
+
+    button_widget = Button(
+        frame_widget, text="Enviar",
+        command=lambda: send_message(
+            client_socket, username,
+            text_widget, entry_widget
+        )
+    )
+    button_widget.pack(side=RIGHT, padx=5, pady=5)
+
+    users_widget = Button(
+        window, text="Listar usuarios",
+        command=lambda: list_users_request(client_socket))
+    users_widget.pack(padx=5, pady=5)
+
+    exit_widget = Button(
+        window, text="Salir",
+        command=lambda: exit_request(client_socket, username, window))
+    exit_widget.pack(padx=5, pady=5)
+
+    thread = th.Thread(
+        target=receive_message,
+        args=(client_socket, text_widget)
+    )
+    thread.daemon = True
+    thread.start()
+
+    window.mainloop()
+    client_socket.close()
+
+
+if __name__ == '__main__':
+    client_program()
diff --git a/python-ofensivo/11_chat_cifrado_E2E/oveja-negra.ico b/python-ofensivo/11_chat_cifrado_E2E/oveja-negra.ico
new file mode 100644
index 0000000..13969dd
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diff --git a/python-ofensivo/11_chat_cifrado_E2E/oveja-negra.jpg b/python-ofensivo/11_chat_cifrado_E2E/oveja-negra.jpg
new file mode 100755
index 0000000..0099c98
Binary files /dev/null and b/python-ofensivo/11_chat_cifrado_E2E/oveja-negra.jpg differ
diff --git a/python-ofensivo/11_chat_cifrado_E2E/server.py b/python-ofensivo/11_chat_cifrado_E2E/server.py
new file mode 100644
index 0000000..795c6db
--- /dev/null
+++ b/python-ofensivo/11_chat_cifrado_E2E/server.py
@@ -0,0 +1,83 @@
+#!/usr/bin/env python3
+"""
+SERVER DE CHAT CIFRADO E2E
+"""
+
+import socket as s
+import threading as th
+
+
+def client_thread(client_socket, clients, usernames):
+
+    username = client_socket.recv(1024).decode()
+    usernames[client_socket] = username
+
+    print(f"\n[+] El usuario {username} se ha conectado al chat")
+
+    for client in clients:
+        if client is not client_socket:
+            client.sendall(
+                f"\n[+] El usuario {username} se ha conectado al chat\n\n".encode()
+            )
+
+    while True:
+
+        try:
+
+            message = client_socket.recv(1024).decode()
+
+            if not message:
+                break
+
+            if message == "!usuarios":
+                client_socket.sendall(
+                    f"\n[i] Usuarios conectados: {', '.join(usernames.values())}\n\n".encode()
+                )
+                continue
+
+            for client in clients:
+                if client is not client_socket:
+                    client.sendall(message.encode())
+
+        except:
+            break
+
+    client_socket.close()
+    clients.remove(client_socket)
+    del usernames[client_socket]
+
+
+def server_program():
+
+    host = 'localhost'
+    port = 1234
+
+    server_socket = s.socket(s.AF_INET, s.SOCK_STREAM)
+    server_socket.setsockopt(s.SOL_SOCKET, s.SO_REUSEADDR, 1)  # TIME_WAIT
+    server_socket.bind((host, port))
+    server_socket.listen()
+
+    print(f"\n[+] Server está en escucha...")
+
+    clients = []
+    usernames = {}
+
+    while True:
+
+        client_socket, addr = server_socket.accept()
+        clients.append(client_socket)
+
+        print(f"\n[+] Conectado a {addr}")
+
+        thread = th.Thread(
+            target=client_thread,
+            args=(client_socket, clients, usernames)
+        )
+        thread.daemon = True
+        thread.start()
+
+    server_socket.close()
+
+
+if __name__ == '__main__':
+    server_program()