-: Securing network devices.
Network devices include things like switches, routers,
firewalls, IDS, IPS, and more.
Each of these different devices has its own vulnerabilities
that have to be addressed.
But for the Security+ exam,
we're going to focus on the most common vulnerabilities
across all of these different devices.
The first vulnerability we're going to talk about
is default accounts.
These are accounts that exist on a device
straight out of the box when you buy it.
So, for example, if you buy a small office,
home office wireless access point,
like a Linksys or a D-Link, or something like that,
it's going to have some accounts already established on there.
It might have one like admin or administrator or user,
or something of that nature.
All of these default accounts are very easy to figure out
and very easy to guess.
And so, it's important for you to actually change these names
so that they're not something that an attacker
can easily guess.
And then, all they have to do is guess your password.
Now, this applies to your organizations, as well.
You want to make sure that your naming schemes
aren't really easy to guess.
Unfortunately, though, most organizations are going to use
a common naming scheme for all of their users.
For example, most organizations like to use
first name dot last name.
So, if your name was Jason Dion, like me,
you're Jason.Dion@yourcompany.com.
Or sometimes they'll do something like
jdion@yourcompany.com, where it's the first letter
and the last name.
Any of these make for a great, normal, easy to understand
naming scheme.
That makes operations very easy.
But it also makes it fairly easy to guess.
Because if I see that Jason.Dion@whatever.com is one email,
then I can probably guess that Susan.Smith is also there.
Or whoever else I'm dealing with.
You want to make sure you're thinking about this
and you're starting to add diversity,
and making sure that those default usernames are changed.
Now, the next thing you want to think about
is the device username, as well.
There's defaults for this, too.
I've seen people call them router or switch
as the usernames.
That's not a good plan, either.
When you're creating a device account,
you want it to be something more complex.
So, maybe it's rtr for router,
with a couple of numbers after it.
Something that's not easily guessable.
That's what I'm talking about here
as we try to change these default accounts.
The next issue we have goes right along
with default accounts, it's weak passwords.
Don't leave passwords as their default.
For instance, those Linksys routers we all have,
they're admin for user, admin for password.
That is horrible.
We also don't want to use any words
that are in the dictionary.
Your passwords need to be long, strong, and complex,
with at least 14 characters long, upper case, lower case,
special characters, and numbers.
By having this mixture, it's going to increase the time
it takes to brute force that password,
and make it much harder for an attacker
to break in to your network.
So, for example, if I have the password of password,
which is all lower case, I'm only using 26 different options
because lower case letters are A through Z.
And so, if I look at that, that's considered a weak password.
If I add some upper case to it, now I have 52 characters
because I have upper case and lower case.
So, I have something like PaSSworD,
where the P, the S's and the D's are upper case
and the other letters are lower case.
If I want to make it even more secure,
I can add numbers to that.
And I'll change out the S's for fives
and the Os for zeroes, things like that.
And this is going to give us more choices, again,
because we have 26 lower case, 26 upper case,
and 10 numbers, zero through nine.
But, if we want it to be the best and most secure
that it possibly can be, we want to add symbols to this, too.
And so now, we're going to get something like
70 different options.
We have upper case, we have lower case,
we have special characters, and we have numbers.
And so, by getting this complex password here,
that's written as P@$5w0rd, it's much harder to break
than the old password of P-A-S-S-W-O-R-D.
Now, of course, none of these options are good ones, right?
Because password is a common name
and all these variations are pretty much known by attackers.
And, again, this is only eight characters.
But I'm trying to save some space on the screen.
You're getting the idea, though.
The more complex the password is, and the longer it is,
the harder it's going to be to break,
and it's going to be giving you more security to your networks,
and that's going to help you secure
the weak password vulnerability.
The third issue that we have is privilege escalation.
A privilege escalation occurs when a user is
able to gain the rights of another user
or an administrator.
If your devices aren't up-to-date
on their firmware or updates,
you could have bugs that could be exploited by an attacker.
So, if they can break in as a standard user,
and then escalate up to the root or admin-level account,
and they can then take over your device.
That's the idea with privilege escalation.
Now, privilege escalation can happen one of two ways.
It can happen vertically or horizontally.
When it happens vertically,
it goes from a user up to an administrator account.
It goes upward, right?
Now, if we talk about going horizontally,
privilege escalation then goes from one user
to another user.
So, if you and I both work in an organization
and we both have user accounts,
and I break into your account,
that's considered a horizontal privilege escalation.
We do that a lot of times as a way of lateral movement
throughout the network until we can find a way
to escalate vertically up.
If I can get into your account, I can run things as you
and you're going to take the blame
if I'm doing something wrong.
Our next vulnerability is backdoors.
A backdoor is way of bypassing the normal authentication
that exists in a system.
These devices that we use are made up of
lots of hardware and lots of software.
Think about your router or your switch.
It's got its own operating system,
it's got its own chips inside of it.
Do you know who made that device?
Which manufacturing plant overseas might have embedded
a little something extra in the code,
or a little something extra of a chip
inside your router or switch?
You really have no way of knowing that, right?
And according to recent news reports,
some believe that nation states have been doing just that.
To prevent this, you need to implement
good supply chain management.
You need to understand where your devices are coming from,
and who's been getting them.
So, if you're going to buy a Cisco device,
you should probably buy it from Cisco directly,
and not buy it from some third-party manufacturer
that has a knockoff clone that's maybe a little bit cheaper.
You want to make sure you're getting good devices
from companies you trust.
Next, we have network attacks,
and network attacks can simply happen all the time, right?
We've talked about this a lot
in the last section of the course.
We talked about all the different ways
you could do network attacks.
Well, to prevent these from occurring, you need to ensure
you have a good intrusion prevention system in place,
you have a properly-configured firewall,
and good network segmentation,
as well as ensuring that all your devices are up-to-date
with their firmware and their updates.
If you can do this, you can minimize
a lot of the vulnerabilities that are out there.
Another big vulnerability, especially in networking devices,
is Telnet.
Some organizations out there are still using Telnet.
If this is your organization, I want you to stop now.
Telnet is horrible.
It is unsecure and it passes your information in the clear.
Meaning it's not encrypted.
Anyone who's on that network can see your usernames,
your passwords, and the commands you're sending.
And this puts the entire network at risk.
Turn off Telnet immediately and switch to SSH instead,
which is Secure Shell that uses good encryption
between your device and the device you're trying
to take remote control of.