How to build a continuous security monitoring program from scratch
How to build a continuous security monitoring program from scratch
Security is no longer a one-time check — it's a real-time challenge.
With hybrid work, cloud-native stacks, and constant change, your infrastructure is always evolving. So should your security strategy.
That's where continuous security monitoring (CSM) comes in.
It helps you detect risks, misconfigurations, and suspicious behaviour as they happen, not weeks later during a quarterly audit.
What is continuous security monitoring?
Continuous security monitoring is the practice of:
- Observing your systems, networks, and assets in real time
- Identifying misconfigurations or vulnerabilities as they appear
- Responding to threats before damage occurs
Think of it as going from snapshot-based security to security as a live stream.
CSM supports goals like:
- Early detection of breaches or lateral movement
- Real-time compliance tracking (e.g. GDPR, ISO 27001)
- Reduced mean time to detect (MTTD) and respond (MTTR)
Key components of a continuous monitoring program
1. Asset visibility and inventory
You can't monitor what you can't see.
Start by mapping all your:
- Domains, subdomains, and DNS records
- IPs and cloud assets (AWS, Azure, GCP)
- Applications, endpoints, and exposed services
2. Vulnerability and misconfiguration scanning
Regular scanning is critical — but must evolve into continuous scanning as new services come online.
Focus on:
- Open ports
- Default credentials
- Public buckets or exposed databases
- IAM permission drift
3. Behaviour and anomaly detection
Not every risk is a misconfigured asset.
CSM also includes:
- Login pattern anomalies
- Unusual outbound traffic
- Suspicious API behaviour
4. Alerting and triage
Too many alerts = alert fatigue.
Build smart thresholds and prioritise:
- Critical risks to production environments
- Publicly exposed services
- Assets with customer data or sensitive IP
Use tags, risk scores, and context to make alerting actionable.
5. Dashboards and reporting
Dashboards should offer:
- Asset and exposure trends
- Alert volume and resolution times
- Compliance status by framework
Make data shareable across teams: security, DevOps, product.
Real-world examples of what to monitor
External attack surface
- New subdomains or IPs appearing
- Changes to exposed ports or services
- SSL certificate updates or mismatches
Cloud environments
- New storage buckets
- Permission changes to IAM roles
- Public exposure of staging environments
SaaS or internal tools
- Admin logins from new geographies
- Disabled 2FA or MFA on key accounts
- API keys pushed to public repositories
Getting started with limited resources
You don't need a 24/7 SOC to get value from CSM.
Start small, scale smart:
Step 1: Inventory your external assets using a platform like Tresal
Step 2: Set up automated scans for open ports, misconfigs, and changes
Step 3: Define 5–10 high-priority alert conditions
Step 4: Route alerts to Slack, email, or your ticketing system
Step 5: Review weekly trends to spot drift or exposure creep
How Tresal helps you monitor what matters
Tresal is built to help growing European teams:
- Discover new and forgotten assets before attackers do
- Monitor changes to your external footprint in real time
- Get alerts for risky exposures and misconfigurations
No complex integrations. No heavy setup.
Just actionable visibility, designed for scale-ups and SMBs.
Conclusion
Continuous security monitoring doesn't have to be overwhelming.
With the right tools and a phased approach, any organisation can gain real-time visibility into its risk surface.
Start with your assets. Add continuous scanning. Automate alerting.
Then improve it over time.
Want to know what's exposed right now in your environment?
Tresal shows you what attackers see — so you can act before they do.
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Matthias
CPO & Cyber Security Enthusiast
CPO bridging product strategy and cybersecurity—sharing insights on secure product design, attack surface awareness, and platform risk management.
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