Network Penetration Testing

External perimeter and internal network testing, including the Active Directory attack paths that turn one workstation into domain-wide access.
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Definition

What is network penetration testing?

Authorized testing of your network infrastructure by operators who try to break in and then move. External testing works from the internet against your perimeter. Internal testing starts from a position an attacker would realistically reach, usually a compromised workstation or a set of standard user credentials, and pursues privilege escalation and lateral movement toward something that matters. The distinction from vulnerability scanning is not thoroughness but consequence: a scanner reports that a service looks outdated, while a penetration test proves whether that service actually gives an attacker a foothold, what the foothold reaches, and which three individually unremarkable findings chain into a domain compromise.

Services

What does a network penetration test cover?

External perimeter
Internal network
Active Directory attack paths
Segmentation and lateral movement
Cloud and hybrid networks
Wireless

External perimeter

Everything reachable from the internet, starting with discovery rather than the list you gave us. Forgotten subdomains, a staging environment that was never meant to be public, an acquisition's netblock nobody inventoried, exposed management interfaces, and VPN or remote access endpoints. The most common serious external finding is not an unpatched service; it is an asset the client did not know was theirs.

Internal network

Testing from the position an attacker actually occupies after a successful phish: a standard user on a standard workstation. From there we pursue credential exposure in shares and scripts, service misconfiguration, unconstrained delegation, certificate services abuse, and the flat-network reality that most segmentation diagrams do not survive contact with.

Active Directory attack paths

The area where internal tests earn their fee. Delegation abuse, Active Directory Certificate Services misconfiguration, Kerberos attack classes, nested group sprawl that quietly grants domain rights, service accounts with excessive privilege and passwords set in 2019, and tiering models that exist in documentation but not in group membership. We report the shortest path to domain admin and the specific link that breaks it.

Segmentation and lateral movement

Whether your network boundaries hold under an attacker who is already inside one of them. We test reachability between zones you believe are separated, whether a compromised user workstation can touch production databases or backup infrastructure, and whether the jump hosts and privileged access paths are actually enforced or merely conventional.

Cloud and hybrid networks

Most networks are now hybrid, and the interesting failures live at the seam. We test the trust relationships between on-premises identity and cloud tenants, the network paths that a cloud workload has back into corporate, metadata service exposure, and the privilege escalation routes that turn a compromised cloud role into broader access. Attackers cross this boundary; testing should too.

Wireless

Where you have physical offices worth testing: authentication weaknesses, guest network isolation that leaks into corporate, rogue and evil-twin exposure, and pre-shared keys that have not rotated since the office opened. Scoped on request rather than assumed, because for many distributed companies wireless is no longer a meaningful attack surface and the budget is better spent on identity.

Our approach

Our approach

01

Enumerate before exploiting

We build our own picture of your estate rather than testing only the scope list, then reconcile the two. The difference between those pictures is often the most valuable page in the report, because unknown assets are where incidents actually start.

02

Chain findings into real paths

Individual findings rarely tell you much. A readable file share plus a service account password plus an over-permissioned group is a domain compromise. We report the chain, not just the links, and we rate severity on where the chain ends.

03

Prove impact, stop at the boundary

We exploit to the depth that demonstrates real consequence and no further, capture an evidence chain, and halt where the rules of engagement say to. Destructive techniques and denial of service are excluded unless separately authorized in writing. Critical findings reach you the day we prove them.

04

Retest, then measure detection

Findings close on verified retest, which is included rather than billed separately. Where you want the harder answer, we replay the successful path with your defensive team watching and report what your tooling caught and what it missed.

contact us

Need a network test that goes past the scanner?

Tell BD Emerson about your estate size, whether Active Directory is in scope, and your compliance deadline, and we will scope it precisely.

Our Advantage

Why BD Emerson for network testing

Operators, not scan output

Automated tooling handles discovery and regression. Humans do the chaining, the credential work, and the Active Directory analysis that decides whether a finding matters. You get committed operator hours, and we will tell you how many before you sign.

Reports engineers can act on

Every finding carries severity, a CVSS v3.1 vector, evidence, reproduction steps, and a specific fix, plus an attack-path narrative and a MITRE ATT&CK map. We also report the attacks that failed because a control worked, so you know what to keep funding.

One team across every asset class

Network, web, API, mobile, cloud, and identity under one methodology. Attackers move across those boundaries, so the team that tests you should too. Splitting asset classes across vendors is how cross-domain attack paths stay invisible.

Reviews

What our customers say

Great consulting firms for scaling security, compliance, and appsec.

Outstanding partner in Technical and Cyber Due Diligence

Appsec maturity and application hardening.

BD Emerson helped us simplfiy our compliance management.

BD Emerson did such a phenomenal job. What started as privacy support quickly became a full partnership across compliance, engineering, and even business operations. They’re embedded with our team. They understand our product. They move fast. They’re simply invaluable.

Adam Ben Jacobs

CTO @ OneStep GPS

Great consulting firms for scaling security, compliance, and appsec.

Outstanding partner in Technical and Cyber Due Diligence

Appsec maturity and application hardening.

BD Emerson helped us simplfiy our compliance management.

BD Emerson did such a phenomenal job. What started as privacy support quickly became a full partnership across compliance, engineering, and even business operations. They’re embedded with our team. They understand our product. They move fast. They’re simply invaluable.

Adam Ben Jacobs

CTO @ OneStep GPS

We had a hard time finding the right company to partner with in support of our compliance journey. Some vendors sell the idea that they do the work, but then you end up doing everything. The ambiguity is what killed our last project. BD Emerson’s team has such great technical knowledge and understands the standard so well that they made us comfortable with moving fast. This has led to us closing major enterprise customers that were previously out of reach because of security and compliance.

Tom Watkins

CEO @ AMI AssetTrack

Lead an enterprise initiative to overhaul the organization's technology stack from ecommerce, corporate tech, and corporate security.

Supported ISO 42001 exercise and served as internal auditor.

Rubrik's privacy and compliance team began with the backbone of BD Emerson. BD Emerson supported building out the privacy program, GRC (ISO 27001, SOC 2, CMMC, FedRAMP), and the appsec function.

We needed a partner who could move quickly, without sacrificing precision. BD Emerson brought the expertise, structure, and speed we were looking for. Their team became an extension of ours, embedding themselves across the organization, guiding us step by step, and giving us confidence in areas we hadn’t tackled before. The internal audit they conducted was so detailed that even the external auditors called it out. Achieving ISO 27001 with zero nonconformities says everything you need to know about the quality of the partnership.

Walid Souilem

CTO @ FGI Worldwide

We had a hard time finding the right company to partner with in support of our compliance journey. Some vendors sell the idea that they do the work, but then you end up doing everything. The ambiguity is what killed our last project. BD Emerson’s team has such great technical knowledge and understands the standard so well that they made us comfortable with moving fast. This has led to us closing major enterprise customers that were previously out of reach because of security and compliance.

Tom Watkins

CEO @ AMI AssetTrack

Lead an enterprise initiative to overhaul the organization's technology stack from ecommerce, corporate tech, and corporate security.

Supported ISO 42001 exercise and served as internal auditor.

Rubrik's privacy and compliance team began with the backbone of BD Emerson. BD Emerson supported building out the privacy program, GRC (ISO 27001, SOC 2, CMMC, FedRAMP), and the appsec function.

We needed a partner who could move quickly, without sacrificing precision. BD Emerson brought the expertise, structure, and speed we were looking for. Their team became an extension of ours, embedding themselves across the organization, guiding us step by step, and giving us confidence in areas we hadn’t tackled before. The internal audit they conducted was so detailed that even the external auditors called it out. Achieving ISO 27001 with zero nonconformities says everything you need to know about the quality of the partnership.

Walid Souilem

CTO @ FGI Worldwide

BD Emerson didn’t just help us meet our compliance goals; they integrated security and privacy into the core of our operations. I highly recommend BD Emerson to anyone seeking SOC 2 or GDPR compliance, or simply looking to enhance their security team and boost customer trust in their product and services. Their dedication and expertise have been invaluable to our success.

Padraig Reilly

CEO, Boxcore

BD Emerson understood our business requirements and worked side-by-side with us. The policies and controls we developed together not only meet compliance standards but improve how we operate day to day.

Matt Meierdierks

IT Manager, Lincoln Industries

From day one, BD Emerson brought urgency, clarity, and a sharp understanding of what truly matters to our business — earning and keeping customer trust. They went beyond helping us meet compliance requirements; they helped build a foundation for secure, scalable growth. That kind of partnership is rare.

Jason Marker

CEO @ LifeLenz

BD Emerson didn’t just help us pass an audit—they helped us build a sustainable culture of security.

Alexey Indeev

CTO Spare

BD Emerson was essential in helping our company navigate the daunting process of leveling up our security infrastructure. BD Emerson’s impressive expertise and confidence throughout the process helped our team exceed HIPAA and SOC 2 Type 1 standards quickly, distilling what can be an overwhelming process into a streamlined, organized effort. From day one they began adding value and getting us on course. With their help we delivered on a massive security overhaul with both extreme efficiency and thorough attention to details. Because of BD Emerson’s support, we’ve increased our clients’ trust in Titan Intake and the life-changing work it accomplishes for those seeking specialist referrals.

Patrick Bruce

CEO, Titan Intake

BD Emerson didn’t just help us meet our compliance goals; they integrated security and privacy into the core of our operations. I highly recommend BD Emerson to anyone seeking SOC 2 or GDPR compliance, or simply looking to enhance their security team and boost customer trust in their product and services. Their dedication and expertise have been invaluable to our success.

Padraig Reilly

CEO, Boxcore

BD Emerson understood our business requirements and worked side-by-side with us. The policies and controls we developed together not only meet compliance standards but improve how we operate day to day.

Matt Meierdierks

IT Manager, Lincoln Industries

From day one, BD Emerson brought urgency, clarity, and a sharp understanding of what truly matters to our business — earning and keeping customer trust. They went beyond helping us meet compliance requirements; they helped build a foundation for secure, scalable growth. That kind of partnership is rare.

Jason Marker

CEO @ LifeLenz

BD Emerson didn’t just help us pass an audit—they helped us build a sustainable culture of security.

Alexey Indeev

CTO Spare

BD Emerson was essential in helping our company navigate the daunting process of leveling up our security infrastructure. BD Emerson’s impressive expertise and confidence throughout the process helped our team exceed HIPAA and SOC 2 Type 1 standards quickly, distilling what can be an overwhelming process into a streamlined, organized effort. From day one they began adding value and getting us on course. With their help we delivered on a massive security overhaul with both extreme efficiency and thorough attention to details. Because of BD Emerson’s support, we’ve increased our clients’ trust in Titan Intake and the life-changing work it accomplishes for those seeking specialist referrals.

Patrick Bruce

CEO, Titan Intake

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FAQ

Frequently asked questions

How is this different from a vulnerability scan?

Do we need external testing, internal testing, or both?

Do you test Active Directory specifically?

Will testing disrupt production?

How often should network testing happen?

Does this satisfy SOC 2, ISO 27001, or FedRAMP?

What do we receive?

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