welcome back to intermediate endpoint security course. And in this lesson, I'm going to talk about protecting the harder off the PC.
So in this video, particularly, I'm going to just concentrate on what you five by us is and why it has to be protected.
So, uh, definition of you, your five buyers is Ah, it's a shortcut from unified extensible firmer interface.
So what? What we do have We have a hardware as a bottom layer of the device. It's pure harder, and it cannot do anything.
Then they have firmer of components like we have firmer on the hard drive. We have firmer on maybe, um, assess the and then we have you If I bias and your five bios is basically a small operating system
that works on the low level and essentially is there
to provide communication between operating system and harder components.
So, in modern operating systems like Windows 10 although there is a way that you can access directly, harbor usually just call from os your five function and say, Okay, I need this data read from
hard drive and you get it or I need something from memory and you get it or I need to send something to video card and it's done.
So this is pretty much how the things work. Okay, there are ways to have some kind of direct access to harbor, especially because legacy applications work that way. But essentially printing printer manufacturers. Processor manufacturers always manufacturers want to avoid
and to have standardised the ah methods of processes for contacting, uh, harder so that you can eventually have a softer and operating system that is absolutely hardware independent
outside eso under DDOS. But in the last layer off, it's a privilege or ability to access something. You have applications. So applications Doctor, I so esque talks to you. If I If I talks to hardware and firmer on, the harder
also helps communicate these things. So this is a
This is how the modern piece he works and unify is essential part of that architecture. So it's in every new PC for some time.
As I said it, texts like link between operating system and the harder and what is most important is it operates in high level highest level off priority.
Eso wise, you, if I so important from security standpoint,
essentially it can do anything that are operating system can do. So if you if you write the if you put something in the in the U If I you can make it,
you know, play movies on on your display It is possible so it can access
You can send delete and edit files. And what is the most important issue from security sponsors standpoint is that
these actions are not detectable from inside the operating system. So,
operating system When you when you start your PC there a certain portion off memory that is reserved for you. If I and this portion of memory cannot be seen from operating system, no application within operating system, no process,
no service in the operating system. Connects. Is this memory?
That means that anti where software cannot see what's happening in the Bible. So if you have a mull over inside the bios,
no software solution can access it and detect that activity.
this is this is rather scary if you when you find that allowed for the first time. Um, and the reason why there is not so much talk about these things
is that unfortunately all of our security industry has been driven by people who makes some kind of software solutions.
Unfortunately, because these people essentially cannot do anything about detecting or preventing by swears is from functioning,
they're just not mentioning that.
And in this situation, a zit is today. There is very little awareness off the importance of protecting you if I
and, uh, the ways to do it. So I'm going to try to talk much more about this later during this course.
So with the end of this lesson, let's do a short learning trick. The question is, what does your if I as a shortcut stand for? So is it unified? Extendable extensible Firmer interface is It's universal Extensible Firmer interface
Or is it your unified external firmer interface?
And the answer is unified extensible firmer interface.
So in this, uh, video you have learned about,
what is your if I and what is the security importance off you if I or you? If I bias has be, call it
just to make a short remark at the end. In the past, BC's had bias, and it was much lower level software that was also running on Britain system. It had similar characteristics of fear. If I
But what is the most important thing? It was usually written in machine code there just a couple of companies
that were writing bios. Today you write, you can write your if I using C plus plus, for example, or
some kind off very, very high level operators programming language, and then you can create the cold that can run on the processes. So this this is the biggest issue with hacking you if I bios
is that the knowledge needed to do that
is much more widely spread than it was in the past when we had just a plain old bias.