In this lecture we’ll discuss how to configure the WiFi Network for Maximum Security and mitigate
the attacks we have seen. To secure a wireless network
we have to secure both the access point or the wireless router and the wireless communication between
the AP and the WiFi clients. In this lecture
I'll show you how to configure a wireless router for maximum security. For other models
there is probably another interface but the options and the concepts are the same.
To secure the WiFi router we should follow the next steps.
Change the default password of the router with a strong one; each home wireless router comes with a
default username and password.
If you do not change it with a strong one
a hacker could log into your router and see the wireless password or even change it.
Connect to the WiFi router only using https.
If you use http, like in this example, the connection is not secure and the hacker could launch a simple
attack of type Men in the Middle like arp poisoning and capture the log in password.
So the strong password you have set will be of no use.
I am logged into the router.
Disable remote administration of the router which means connecting to the router from the Internet.
This way you avoid denial of service or brute force attacks to your router. In this example
the remote management function is disabled configure it from your local wired or wireless network; disable
services that are running on your router but are never used; for example if you do not use Telnet
or SSH to connect to the router disable them; each running service is a security vulnerability. Update
the firmware to its latest version available to avoid the exploitation of known vulnerabilities.
Many vendors release new updates to patch vulnerabilities that have been previously discovered.
Check regularly on the official website if there is any firmware available for your model. These were
the most important security settings for your router.
Depending on the router model there could be other settings available as well.
You could simply search on Google for secure and your router model. To secure the wireless communication
between the WiFi router and the clients
you should use only WPA with a very strong password.
Do not use WEP no matter the circumstances.
A strong WPA2-PSK password means at least 12 random characters or 6 random words.
This isn't a good password
for example; it's a dictionary word and we've already cracked it in the previous lecture. At the end of
the day
the wireless security is as strong as the WPA 2 password. Disable WPS or WiFi protected setup.
WPA is a very secure protocol as long as the password is strong enough.
That means at least 12 random characters or 6 random words.
This can be a bit inconvenient as you have to enter this long passphrase on each new device that connects
to the network. WiFi protected setup or WPS was created to solve this problem.
When you connect to a router with WPS enabled you'll see a message saying you can use an easier way
to connect rather than entering your WiFi passphrase.
There are two different ways to connect to the WiFi router using WPS: using a PIN configured on the
router or using the push button connect. A PIN is an eight digit number that you need to enter on your
devices to connect. the WPS pin is very easy to brute force.
The second option is the push button connect. Instead of entering a PIN you simply push a physical button
on the router after trying to connect.
This is more secure but anyone with physical access to the router could push the button and connect
even if they don't know the WiFi password. WPS should be disabled.
Keep this in mind, it's really important! You could also use MAC address filtering, only if possible, but
do not rely too much on it.
MAC address filtering allows you to define a list of devices and allows on your WiFi network only
those devices. You can implement
this feature only on small private networks where all clients are known in advance.
However this is not a strong security measure because MAC addresses can be easily spoofed. All an attacker
has to do is monitoring WiFi traffic using a tool like airodump-ng, examine a packet to find to
the MAC address of an allowed device, change their devices MAC address to that allowed the MAC address
and connect in that device's place.
You may be thinking that this will not be possible because the device is already connected but a
deauthentication attack that disconnects a device from the WiFi network will allow an attacker to reconnect
in its place. WPA2 with a strong password should be enough.
Imagine that someone that knows how to capture the WPA2 4-way handshake and crack the password will
have no difficulty bypassing the MAC filtering security feature.
Okay that's all.
There is no network that's 100 % secure but implementing these options you are seeing right now
will make your WiFi network secure enough in most cases.