In this lesson,
we're going to discuss network and infrastructure controls,
specifically focused on network segmentation
and infrastructure security controls,
and how to recommend appropriate remediation
after a pen test.
First, let's define network segmentation.
Network segmentation is a practice
of dividing a larger network into a smaller,
isolated segment or subnet.
This is done to enhance security, improve performance,
and manage traffic more effectively.
By segmenting a network, you can limit the spread
of malware, control access to sensitive data,
and reduce the attack surface available
to potential intruders.
In organizations with sound network segmentation,
you'll typically see admins on one VLAN
and other departments such as HR, Accounting, et cetera,
on their separate VLANs.
The most basic aspect of network segmentation
is the separation of critical systems
from less critical ones.
For example, you might segment your network
so that your financial systems are isolated
from your general office network.
This way, even if an attacker gains access
to the office network, they cannot easily reach
the financial systems.
A key characteristic of effective network segmentation
involves the use of firewalls, VLANs, as mentioned earlier,
and access control lists, also known as ACLs.
Firewalls can be used to enforce
strict access policy between segments.
VLANs allow you to create separate broadcast domains
within the same physical network.
And ACLs provide granular control over which devices
and users can access specific network segments.
Now, let's move on to infrastructure security controls.
Infrastructure security controls are measures put in place
to protect the physical
and virtual components of your IT environment.
This includes things like servers, storage systems,
network devices, and other hardware and software assets.
These controls are designed to ensure the integrity,
confidentiality, and availability of your infrastructure.
Examples of infrastructure security controls include
implementing strong authentication mechanisms,
using encryption to protect data at risk and in transit,
and regularly updating and patching systems
to fix known vulnerabilities.
Additionally, employing intrusion detection
and prevention systems can also help monitor
and block malicious activities.
So why is this important?
Network segmentation and infrastructure security controls
are critical because they help contain security incidents,
prevent unauthorized access,
and protect sensitive information.
Without these controls,
attackers can laterally move across your network,
access critical systems, and exfiltrate valuable data.
So now, how do you recommend appropriate remediation
after a pen test for network segmentation
and the infrastructure security controls?
First, we start by reviewing
the current network architecture:
Identify any flat network structures
that lack segmentation and propose a redesign
that includes the segmentation of critical systems,
set of data areas, and different departments;
implement VLANs and configure firewalls
to enforce access policies between the segment;
and use access control list to define which users
and devices can access specific segment.
Next, assess the existing infrastructure security controls.
Ensure that strong authentication mechanisms,
such as multi-factor authentication, are in place.
Verify that data encryption
is used for both data at risk and data in transit.
Next, we need to conduct regular vulnerability assessments
and apply patches and updates properly.
Then, we need to deploy and configure intrusion detection
and prevention systems to monitor the network traffic
and block suspicious activities.
And lastly, make sure we educate the IT staff
and users about the importance of these controls
and provide training on best practices
for maintaining a secure infrastructure.
So remember, network segmentation
and infrastructure security controls are essential practices
to enhance your network security posture.
By segmenting your network
and implementing robust security controls,
you can limit the spread of attacks, protect sensitive data,
and ensure the integrity and availability of your systems.
Following these remediation recommendations
will help you address the vulnerabilities identified
during a pen test and maintain a secure
and resilient infrastructure.