Network Security Audit [+ Free Checklist]

This guide walks through what a network security audit actually involves, breaks the process down into a practical, step-by-step network security audit checklist, and shows you how to turn the results into action. It's built around zero trust principles — verify everything, trust nothing by default — because that's the model most resilient IT and security teams are moving toward. And if you'd rather not rebuild the checklist from scratch, we've put the whole thing into a free downloadable PDF you can hand straight to your team.

If you're running IT for a small or midsize business, or managing a hybrid team spread across home offices, coworking spaces, and branch locations, this matters more than ever. Every additional device, cloud app, and remote connection is another potential entry point. A structured audit is how you keep that sprawl from turning into risk.

What Is a Network Security Audit?

A network security audit is a comprehensive, systematic evaluation of your organization's IT infrastructure, policies, and controls — done to identify vulnerabilities, confirm compliance, and verify that your defenses actually match your risk. It's not the same as troubleshooting a slow connection or investigating a single incident. Ad-hoc fixes solve the problem in front of you; an audit is proactive and structured, designed to surface the problems you don't already know about.

A thorough network infrastructure and security audit looks at everything connected to your environment: on-premises servers, cloud resources, firewalls, VPNs, endpoints, and the access permissions tied to each one. That scope is exactly why audits matter more for organizations with remote employees, BYOD policies, or sensitive regulated data — the more variable your environment, the more places a weakness can hide, and the more valuable a regular audit becomes. For a closer look at how VPN-specific reviews fit into this picture, see our detailed VPN audit procedures.

Network Security Audit Checklist: Core Components

Here's the core of it — a practical checklist you can work through section by section. Each area below covers what to check and why it matters. If you manage access at scale, pair this with our access control templates for security reviews to standardize how permissions get documented across teams.

1. Classify Asset Inventory

You can't secure what you don't know you have. Start by mapping every device, endpoint, cloud resource, and piece of critical infrastructure connected to your network — including the shadow IT that crept in without a formal request. Once everything is mapped, prioritize assets by risk and exposure, so your limited time and budget go toward the systems that would hurt the most if compromised.

• Inventory all servers, endpoints, IoT devices, and cloud instances
• Flag unmanaged or unauthorized ("shadow IT") devices
• Rank assets by sensitivity of data and business impact
• Document ownership for every asset on the list

Understanding where your real exposure sits is foundational to the rest of the audit — for more on this, see our guide to understanding attack surface security.

2. Review Access Controls and User Permissions

Next, scrutinize who can get to what. Over time, access rights tend to accumulate — someone gets temporary access to a system for a project and keeps it long after the project ends. Review role-based access controls and confirm the principle of least privilege is actually being enforced, not just written down in a policy document.

• Audit user roles against current job functions
• Enforce least-privilege access across systems and data
• Flag unused, orphaned, or excessive permissions
• Confirm offboarded employees' access was fully revoked

This is a good place to lean on standardized documentation — our access control templates for security reviews can help you track findings consistently across departments.

Of note, this is where many businesses fall short. In fact, in a recent survey, we found that 40% of employees had access to sensitive data they didn't need and 73% of orgs are slow to revoke access when roles change. Get more details in our survey here. 

3. Look at Network Configurations and VPN Policies

With assets and access mapped, turn to how traffic actually moves through your network. Verify VPN settings and confirm multi-factor authentication is enforced across all users, not just a subset. Check site-to-site connections between offices or data centers, and review firewall and router rules for anything outdated or overly permissive.

• Confirm MFA is enforced for all VPN and remote access
• Review firewall and router rule sets for outdated entries
• Audit site-to-site VPN connections and their encryption standards
• Verify split-tunneling and access policies match current needs

For more depth on this piece of the checklist, see VPNs and network security and our best practices for site-to-site networking.

4. Assess Vulnerability and Patch Status

Unpatched software is one of the most common — and most preventable — causes of breach. Check every system for outdated software, missing patches, and end-of-life applications that no longer receive security updates. Manual tracking doesn't scale past a handful of machines, so this is one area where automated scanning tools genuinely earn their keep.

• Run vulnerability scans across servers, endpoints, and network devices
• Confirm patch management covers OS, firmware, and third-party software
• Flag end-of-life or unsupported systems for replacement
• Schedule recurring automated scans rather than one-off checks

5. Monitor Log Management

You can't investigate what you didn't log. Confirm that logging is centralized and gives your team visibility across devices, rather than living in a dozen disconnected systems. Logs serve two purposes here: real-time detection of suspicious activity, and forensic analysis after the fact if something does go wrong.

• Centralize logs from network devices, servers, and applications
• Set alerting thresholds for anomalous or suspicious activity
• Confirm log retention meets your compliance requirements
• Test that logs are actually usable during an incident, not just collected

Centralizing this data well makes a real difference during an investigation — see leveraging log streaming for audit trails for more on setting this up.

6. Review Compliance Policies

Finally, check your policies against the compliance frameworks that apply to your business — SOX, HIPAA, PCI DSS, or others relevant to your industry. Documentation gaps are one of the most common findings in this stage: controls that exist in practice but were never written down, or written down and never implemented.

• Map current controls against applicable regulatory frameworks
• Identify and close documentation gaps
• Confirm evidence exists to support each compliance claim
• Schedule a follow-up review ahead of your next audit cycle

If SOX applies to your organization, our SOX compliance guidelines walk through the specifics in more detail.

Best Practices for Running an Effective Audit

A checklist tells you what to check. These practices help make sure the audit itself actually gets done well:

• Set clear goals before you start. Know whether this audit is about compliance, risk reduction, or both — it changes what "done" looks like.
• Assign responsibilities and document every step. An audit with no clear owner tends to stall halfway through.
• Make it repeatable. Quarterly or semiannual audits catch drift before it becomes a real problem — a one-time audit is a snapshot, not a strategy.
• Start small and expand. Pick one department or system, run the process end to end, then scale what worked.
• Build in continuous improvement. Use lightweight "mini-audits" or automated checks between full audits to catch issues sooner.

Whether you're running this manually with an internal network security audit checklist shared across your team or tracking findings in a network security audit checklist excel template, the goal is the same: make the process repeatable enough that it doesn't depend on any one person remembering to do it.

How to Report Results of Your Audit

Findings that live only in someone's notes don't drive change. Compile results into a clear network audit report — a PDF works well for internal circulation or compliance evidence — that separates urgent issues from longer-term improvement opportunities. Nobody needs a 40-item list with no sense of priority.

Once the report exists, use it. A short debrief with the team that owns the affected systems, plus a leadership briefing summarizing top risks and planned fixes, keeps the audit from becoming a document that nobody reads again. For organizations looking to act on these findings systematically, this is often the moment to evaluate a move toward zero trust architecture implementation — since many audit findings (excess access, flat network trust, weak segmentation) are exactly what zero trust is designed to fix.

Take Control of Your Network Security

Regular audits are how you catch vulnerabilities, confirm compliance, and strengthen your security posture before a small gap becomes a real incident. They don't have to be overwhelming — with a clear checklist, the right network security audit tools, and a repeatable process, an audit is a manageable quarterly task rather than a fire drill.

Ready to put this into practice?

1. Download the free checklist and work through it with your team.
2. Start your journey toward Zero Trust with CloudConnexa — OpenVPN's cloud-delivered network security platform built to make audits like this one easier from the start.