In this lesson, we're going to discuss
operating system vulnerabilities.
Operating systems are pivotal in the functioning
and protection of our digital devices
because they bridge the gap between hardware
and software to ensure
that seamless interactions are going to occur.
However, vulnerabilities within operating systems
can pose significant security threats to our systems.
These vulnerabilities include unpatched systems,
zero-day vulnerabilities, misconfigurations,
data exfiltration, and malicious updates.
So let's explore some of the vulnerabilities,
their implications, and the measures that we can adopt
to better secure our systems.
First, we have unpatched systems.
Unpatched systems refer to those operating systems
that have not been updated
with the latest security patches or fixes.
These systems are highly susceptible to attack
because they contain vulnerabilities
that might have been addressed in newer updates.
Since these unpatched systems are missing patches
that protect us from known vulnerabilities,
these systems are going to be considered
to be put at significant risk of an attack
because known vulnerabilities can be matched
with existing exploits
to execute a given attack against those systems.
To overcome an unpatched system vulnerability,
the easiest thing you can do
is to ensure your operating system is up to date.
By regularly updating and patching your systems,
you can very effectively protect
your devices from an attack.
So you should ensure that you have scheduled your systems
to perform automatic updates,
or that you periodically check your systems
to ensure the latest patches have been applied
in order to keep your system secure.
Second, we have zero-day vulnerabilities.
Now, zero days represent vulnerabilities in software
or hardware that are unknown to the developer
and in essence, they're newly discovered vulnerabilities
that have not yet been publicly disclosed yet.
Now, since the developer isn't aware of the issue yet,
they have zero days to fix that issue,
which is where the term zero-day comes from.
Now, to protect against zero-day vulnerabilities,
you should implement security solutions
like a host-based intrusion prevention system,
known as an IPS.
This allows you to detect and block suspicious activities
that may occur on a given system.
Additionally, you should try to maintain a good
security posture through practices like frequent system
and software updates, even if they don't address
an unknown vulnerability, like a zero-day,
because it can still provide additional protection
as a form of defense in depth
against potential zero-day exploits in the future.
Third, we have misconfigurations.
Now, misconfigurations in an operating system
are going to occur when the system settings
are not properly configured,
and this leaves your system vulnerable to exploitation.
These configurations could be due
to default settings that are not being changed,
unnecessary services being left enabled,
or security features being accidentally turned off.
To safeguard against risk associated with misconfigurations,
configuration management tools should be employed
across your organizational network.
These configuration management tools can help us
in standardizing and automating the configuration process
to ensure consistency and the elimination
of human errors inside of your systems.
You should also conduct periodic audits
and reviews of your system configurations to identify
and mitigate potential vulnerabilities
that you can find inside of those systems.
Now, fourth, we have data exfiltration.
Data exfiltration refers to unauthorized data transfers
from within an organization to an external location.
Data exfiltration commonly occurs
when an operating system's vulnerability is exploited
and the attacker attempts to steal your data
without your awareness.
Now, protecting against data exfiltration
involves multiple layers of defense
including the use of encryption
and endpoint protection tools.
Encryption of your data at rest will help to ensure
that even if the data is accessed by an attacker,
that data will remain unreadable and unusable to them.
Also, you can implement endpoint protection tools
on your systems to help monitor
and restrict unauthorized data transfers on those devices.
If you also implement a host-based firewall, for example,
you can then use this to control the inbound
and outbound traffic on a given system
to ensure that your data isn't leaving your system
without proper authorization.
Fifth, we have malicious updates.
Now, normally, we're going to see an update
or a patch as a good thing for our security.
But there are some cases where an attacker's been able
to craft a malicious update to a well-known
and trusted program in order to compromise the systems
of the programs and users.
With a malicious update, the update will masquerade
as a legitimate security update or patch,
but it actually contains some malicious code
inside of it that effectively will inject malware
or an exploit into your system when the update is installed.
Now, to guard against the malicious update,
it's crucial that you only source your updates
from trusted vendors and official channels.
Application allow listing will also be maintained
to ensure that only recognized and safe applications
are permitted to be run on your given system.
Additionally, always verify the authenticity of updates
through a digital signature or a hash
before you install the update on your system.
So remember, while the vulnerabilities
in operating systems can be varied and sophisticated
including unpatched systems, zero-day vulnerabilities,
misconfigurations, data exfiltration,
and malicious updates, your protective measures
don't always have to be complex
in order for them to be effective.
From patching regularly to encryption
to configuration management, we have the ability
to significantly enhance the security
of our devices and our data
by using some common defense in depth measures.