Threat Modeling: Uncovering The Undocumented Risks

Threat modeling is a critical practice in cybersecurity that helps identify potential vulnerabilities and threats before they can be exploited. One often overlooked aspect is the undocumented knowledge—things “everyone knows” but aren’t formally documented. These hidden assumptions can become security blind spots.

You Should Know:

Key Threat Modeling Steps

Identify Assets: Determine what needs protection (e.g., databases, APIs, user credentials).

Example: List critical files in Linux 
find / -type f -perm -4000 -ls  Find SUID files (potential privilege escalation risks)

Map Data Flows: Understand how data moves through systems.

Use tcpdump to monitor network traffic 
sudo tcpdump -i eth0 -n -vvv

Document Assumptions: Explicitly list “common knowledge” that isn’t written down.
Identify Threats: Use frameworks like STRIDE (Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege).
```
Check for open ports (potential entry points) 
sudo nmap -sV -O 192.168.1.1 
```

Mitigate Risks: Apply controls like encryption, access restrictions, and logging.

Enable auditd for logging file access in Linux 
sudo auditctl -w /etc/passwd -p rwxa -k passwd_access

Windows-Specific Commands

Check active processes for anomalies:

Get-Process | Where-Object { $_.CPU -gt 90 }

Verify firewall rules:

netsh advfirewall firewall show rule name=all

What Undercode Say

Threat modeling is not a one-time task but an ongoing process. Undocumented practices often hide the most critical risks—whether it’s a shared password, a legacy script with elevated permissions, or a “temporary” firewall rule left open. Automate checks where possible, and foster a culture where assumptions are questioned.

Expected Output:

A structured threat model document.
Logs of network traffic, file access, and process activity.
Mitigation strategies for identified threats.

Prediction

As organizations adopt more cloud-native and microservices architectures, threat modeling will increasingly rely on automated tools to track dynamic environments. However, human insight will remain essential to uncover the “undocumented” risks.

(Relevant URL: OWASP Threat Modeling Guide)