In this challenge, we're going to keep it just a little simple and go with something a little
bit more rudimentary. Making sure that we can understand the identification of our actual
kernel version number based on the uname command inside of your personal environment or more
specifically inside of our lab environment. Because I want to be able to challenge you
here with understanding if a CVE matches its actual kernel versioning information.
And this will seem a little easy because in practicality it should be. But it's also just
making sure that we understand how to be able to look up and verify vulnerabilities that may not
already be in our vulnerability scans. You see, before we opened up earlier in the skill with
OpenVAS, I actually had to sit down and re-update everything to make sure current definitions were
up to snuff. There have been some definitions added based on the kernel versioning information
inside of our own Ubuntu lab that weren't previously identified and now need to be
properly dimed out. This is good for us pen testers because like we noticed earlier on,
there was a CVE that addressed CIFS as far as mounting a shared folder or file to a remote
system. And in the CIFS case, we're talking about Windows. So if we can take that information and
leverage it against a vulnerability or a known exploit inside of something like Metasploit,
then that's good for us because that makes our job just a little bit easier in terms of actual
research. And aside from going through and using the uname command on the actual Linux system that
we're working on at that time, it's good to be able to take vulnerability assessments through
tools like OpenVAS SNES and also be able to go in tools like Nmap and be able to properly identify
with OS fingerprinting if we can go through and properly identify that kernel. Now again,
there is a separation between the actual operating system and the Linux kernel itself. And to go a
little bit deeper in the weeds on using Linux kernel versions to be able to identify vulnerabilities
and also basic functionalities of different operating systems, what I have here on the
screen with links below is ArchLinux.org. This is a different flavor of Linux that sits on top
of the actual Linux kernel that we've been examining inside of Ubuntu itself. You see,
if I zoom in for us real quick, you can see that their previous release dates and versions of their
particular operating system lines up with the kernel version number. And I'm going to highlight
here for you two rows real quick that use Linux kernel 6.14. One is 0.4 and one is 0.9. So while
the outside of their operating system may look a little bit different, everything under the hood,
especially when we connect over SSH, is going to look exactly the same because we're not worried
about that GUI interface or interaction. And it's not just them. Fedora, one of the more commonly
used POSIX-based operating systems out there, has a whole litany of different kernels, 6.14,
and these are different updates for Fedora, 41, 42, or even 40. And you can see that some of them
are stable, obsolete, or whatever the case may be, like kernel 6.1411300fc42. Different
revisioning numbers, but Fedora being the actual operating system overlay, and that flavor that
sits on top of the Linux kernel, and the actual Linux kernel that you can pick up at kernel.org
of 6.14, so that way you could go in and run the base of the operating system. See, all these
different things come into play because everything that we've been discussing about Linux
insecurities and different things to look at concerning the actual security measures, all play
the same role in these different operating systems across those POSIX-based systems. And that's why
I started off by saying, you always hear about the big three in motor cars and production and
whatnot, but whenever you hear something, let's say like an Audi, that's common enough to where
you know what it is, but not as common here in the U.S. to understand that it has a decent market
share, large enough to where it's actually more than you would expect. But just because you don't
hear Audi and recalls all the time, doesn't mean it's not happening. And if the vulnerability
happens in one version of 6.14 of the kernel, as just our example in this particular skill,
then if that vulnerability can be moved over to a different OS like Fedora to be leveraged
against them as well, because it's the same baseline. And this is very similar to those
old Windows days where you would have DOS 6.22 as the actual operating system on the system itself,
but you would either have Windows 3.11, Windows 95, or Windows 98 sitting on top of those.
And those different versions of Windows were just the interaction between you and the operating
system itself to give it those nice fancy colors, which back in the day I needed. But now that we're
taking a look at this and the thought about insecurity overall, it leads into the actual
final question of this skill to identify CVEs that are aligned with this particular kernel.
And this is the information I want you to keep in mind moving forward into not only the rest
of this course, but also the rest of your courses here at CVT Nuggets. So I hope this
has been informative for you, and I'd like to thank you for viewing.