Firewall & ACL Auditor — Python Security Tool #security #python #linux #networksecurity

Introduction

I built an Automated Firewall & ACL Rule Auditor using Python as my third practical cybersecurity project.

The goal of this project is to automate the initial security review of firewall and ACL rules and identify common configuration weaknesses that may increase security risk.

The project also includes an interactive Tkinter GUI dashboard to make audit results easier to review and understand.

Project Objective

Firewall and ACL rules control which network traffic is allowed or denied. Poorly configured rules can create unnecessary security risks.

Manually reviewing these rules can be time-consuming, especially when dealing with multiple configurations.

This project automates the initial review process by analyzing firewall and ACL rules and identifying potentially risky configurations.

Technologies Used

Python
Tkinter
Firewall & ACL concepts
Security Auditing
Risk Assessment
Security Automation
Git & GitHub

How It Works

The basic workflow is:

Firewall/ACL Rules → Rule Analysis → Security Checks → Findings → Risk Assessment → Report

The auditor examines the configured rules and checks them against predefined security conditions.

When a potentially insecure configuration is detected, the tool records the finding and assigns an appropriate severity or risk level.

Security Checks

The auditor focuses on common firewall and ACL configuration weaknesses, including:

Overly permissive rules
Insecure services
Unnecessary access
Broad source or destination definitions
Potentially risky configurations
Rule-level security findings

The results help identify which rules should receive further security review.

Risk Assessment

A key improvement in this version is the addition of risk assessment.

Instead of only identifying a problematic rule, the auditor provides a risk-oriented view of the findings.

The audit results can include:

Finding
Severity
Risk level
Rule information
Security recommendation

This makes it easier to prioritize findings based on their potential security impact.

GUI Dashboard

I developed an interactive Tkinter-based GUI dashboard to present the audit results visually.

The dashboard provides information such as:

Total firewall rules audited
Security findings
Severity levels
Compliance status
Risk score
Overall risk
Firewall rule statistics

This makes the results easier to understand than reviewing raw output alone.

GUI Dashboard

Why Security Automation?

Security teams may need to review a large number of firewall and ACL rules.

Automation can reduce repetitive manual work and provide a consistent initial security review.

This tool is not intended to replace a complete professional firewall audit. Instead, it demonstrates how Python can automate repetitive security assessment tasks and highlight configurations that require further investigation.

What I Learned

While building this project, I improved my practical understanding of:

Firewall rule evaluation
ACL security concepts
Security auditing
Risk assessment
Python automation
Tkinter GUI development
Security findings and severity classification
Defensive security workflows

The project also helped me understand how security automation can support security operations and GRC-oriented processes.

Project Progression

This is my third practical cybersecurity project.

My current project progression is:

Project 1: Nmap XML Parser v1.1 with MariaDB Integration

Project 2: Network Scanner & Service Enumeration Tool

Project 3: Automated Firewall & ACL Rule Auditor

The projects demonstrate a progression from network reconnaissance and service enumeration toward automated security auditing.

Conclusion

The Automated Firewall & ACL Rule Auditor demonstrates how Python can be used to automate the initial review of firewall and ACL configurations.

By combining rule analysis, security findings, risk assessment, and a GUI dashboard, the project provides a practical approach to identifying potentially risky configurations.

I am continuing to build practical projects focused on Cloud Security, Security Automation, Network Security, and GRC.