From Zero Visibility to a Measurable Security Baseline

Wed, 26 Aug 2026 15:15:28 +0000

Every security team has a “Day Zero” the moment before security tooling, visibility, and processes are in place. You can't confidently answer questions like:

• What devices are on the network?
• Which systems are vulnerable?
• Are our endpoints patched?
• Would we detect a compromise?

That was the starting point for this security lab. The environment had no vulnerability scanning history, no centralized patch management, no endpoint detection, and exposed Windows machines with open RDP. So I approached the problem from the ground up.

1️⃣ Discover Before You Defend
I started with network discovery using Wireshark to identify the devices actually connected to the environment.

2️⃣ Secure the Network With Tailscale
Instead of exposing more management services to the public internet, I established a private Tailscale network.

3️⃣ Establish a Vulnerability Baseline With Wazuh
Next, I deployed Wazuh agents across the endpoints with:
• Vulnerability detection
• File Integrity Monitoring
• MITRE ATT&CK mapping
• CIS Security Configuration Assessment (SCA)

4️⃣ Centralize Patch Management With Action1
Visibility alone isn't enough. Vulnerabilities need to be remediated. I deployed Action1 to centralize patch visibility and deployment while deliberately keeping its findings separate from Wazuh's.

5️⃣ Turn Security Into a Process
I also established severity-based remediation SLAs, critical vulnerabilities were also configured for automated patch deployment and auto-approval.

🔐 Key Lessons
• Discover before you defend.
You need an accurate asset inventory before “coverage” means anything.

• Secure connectivity before expanding management access.
Reduce unnecessary network exposure wherever possible.

• Baseline before remediating.
You need measurable evidence to demonstrate improvement.

• Understand what your security tools actually measure.
Different tools can legitimately produce different results.

• Automate security policies.
A policy sitting in a document doesn't enforce itself.

• Report verified outcomes, not just completed activities.
“Patch deployed” and “vulnerability confirmed remediated” are not the same thing.

👉 Read the full blog post here:

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From Zero Visibility to a Measurable Security Baseline