Penetration Testing Red Team Assessments NGX VAPT Assessments Security Advisory Security Training Architecture Review
Healthcare Capital Markets Banking & Finance Government Telecommunications
Blog Framework Contact Us
EXTERNAL INTERNAL ASSUMED BREACH ACTIVE DIRECTORY
Offensive Security Services

Network Penetration Testing

We test what parts of your infrastructure an attacker can reach from the internet and how far they can go once inside your network. External exposure, lateral movement, and Active Directory attack paths, with each finding proven by hand and written up so your engineers can fix them.

Scope an assessment How it works
Overview

Two vantage points, giving one clear picture of network risk

Network penetration testing answers a question a vulnerability scan cannot: given what you expose and how your internal environment is built, what can a determined attacker actually do? We work from two vantage points, the public internet and the inside of your network, because they uncover different problems. 

Scope

External and internal network testing

External network testing

The external test is done from the public internet, the same position an attacker holds. We visualize what you actually expose, then probe it for weaknesses. The common failures here are boring but dangerous: a forgotten exposed service, a vulnerable VPN gateway, a mail server that allows for user enumeration, or a cloud edge left open after a migration.

  • Exposed services, admin panels, and management interfaces
  • VPN and remote-access gateways, including credential and session handling
  • Mail infrastructure, relay abuse, and information disclosure
  • Cloud: storage buckets, load balancers, and orphaned assets

Internal network testing

The internal test starts inside the perimeter, usually from a normal user's position on the internal network. From there we look at: which computer talks to which, where credentials are cached, and how a single foothold could turn into complete control of the domain or internal environment. This is where flat networks and weak Active Directory hygiene reveal themselves, because one compromised laptop should not put the whole internal environment within reach.

  • Lateral movement across hosts, shares, and trust relationships
  • Privilege escalation on workstations and servers
  • Active Directory attack paths towards domain administrator
  • Flat-network risk and the blast radius of one compromised host
Assumed breach

The foothold.

Phishing works! Given enough staff and enough attempts, an attacker can eventually land on one workstation or walk away with one set of user credentials. An assumed-breach engagement takes that as the starting point.

The value is speed and focus. Instead of spending a long time trying to get in, we spend it trying to advance access: how quickly the foothold spreads, testing if your segmentation works, and whether anyone notices our movements. For most Nigerian organizations this is the sharpest test of internal security, because it mirrors how real intrusions actually unfold.

AI analysis helps sort asset, identity and configuration data across the network. Senior penetration testers use that work to pursue lateral movement and privilege-escalation paths, then verify each reported finding against the environment.

Data centre server racks representing an internal corporate network under penetration testing
Human-led
AI-assisted analysis, with every finding verified by a senior tester
PTES
Mapped to NIST SP 800-115 and OWASP
Retest
Fixed findings re-verified as part of the engagement
Segmentation

Segmentation testing for regulated environments

                     Segmentation is only real if it holds under pressure.

Boundary crossing

We test whether a host in a lower-trust zone can reach systems that should be walled off.

PCI DSS scope

Where segmentation reduces your cardholder data environment, PCI DSS expects it to be tested. We check that the reduction actually holds.

Firewall and VLAN rules

We validate the rules as deployed.

The same approach supports the security-testing expectations under the CBN risk-based cybersecurity framework and the obligations around personal data in the NDPA 2023, which we scope against your specific environment.

Deliverables and retest

What you receive, and how fixes get confirmed


Executive summary written for management and the board
Technical findings with CVSS scoring and reproduction steps
The full attack-path explained from foothold to impact
Remediation guidance arranged by business risk
A retest of fixed findings, included in the engagement
A read-out call with the testers who did the work
Why ClarenSec

Testing done by people you can trust

// 01

Senior penetration testers

Your network is tested by senior penetration testers who hold certifications such as OSCP, OSEP, CPTS, CRTP, ETC not junior testers pointing a scanner at your IP range and exporting the results.

// 02

Attack paths

We chain findings into the path an attacker would take, so you can see which weakness matters most to your business, and fix in the right order.

// 03

Financial-sector experience

Our team has tested banking, capital-markets, fintech, and government networks across West Africa. We know the systems and the regulators that govern them.

FAQ

Network penetration testing questions, answered

What is the difference between external and internal testing?

External testing works from the public internet against the systems you expose: web, VPN, mail, and cloud edges. Internal testing is done from within the perimeter, often from a normal user account, and measures how far an attacker can move towards domain compromise. Most organizations need both, since they answer different questions.

What is an assumed-breach engagement?

It starts from the position an attacker obtains after initial foothold, a single workstation or a set of user credentials. We begin from inside and measure how quickly that foothold turns into wider access. It is the fastest way to test internal detection, segmentation, and privilege boundaries.

Does this help with PCI DSS?

Yes. PCI DSS expects internal and external penetration testing and, where segmentation reduces scope, testing that the segmentation holds. We check whether a system outside the cardholder data environment can reach it, and document the result.

Do you retest after we fix the findings?

Yes. A retest of the fixed findings is part of every engagement. Once your team has worked through fixing the bugs we identify.

Ready to see what your network exposes?

Tell us the size of your environment. We will scope a network penetration test to fit.

Request a scoped quote