/network-101

name: network-101
description: This skill should be used when the user asks to "set up a web server", "configure HTTP or HTTPS", "perform SNMP enumeration", "configure SMB shares", "test network services", or needs guidance on configuring and testing network services for penetration testing labs.
metadata:
  author: zebbern
  version: "1.1"

Network 101

Purpose

Configure and test common network services (HTTP, HTTPS, SNMP, SMB) for penetration testing lab environments. Enable hands-on practice with service enumeration, log analysis, and security testing against properly configured target systems.

Inputs/Prerequisites

• Windows Server or Linux system for hosting services
• Kali Linux or similar for testing
• Administrative access to target system
• Basic networking knowledge (IP addressing, ports)
• Firewall access for port configuration

Outputs/Deliverables

• Configured HTTP/HTTPS web server
• SNMP service with accessible communities
• SMB file shares with various permission levels
• Captured logs for analysis
• Documented enumeration results

Core Workflow

1. Configure HTTP Server (Port 80)

Set up a basic HTTP web server for testing:

**Windows IIS Setup:** 1. Open IIS Manager (Internet Information Services) 2. Right-click Sites → Add Website 3. Configure site name and physical path 4. Bind to IP address and port 80

**Linux Apache Setup:**

# Install Apache
sudo apt update && sudo apt install apache2

# Start service
sudo systemctl start apache2
sudo systemctl enable apache2

# Create test page
echo "<html><body><h1>Test Page</h1></body></html>" | sudo tee /var/www/html/index.html

# Verify service
curl http://localhost

**Configure Firewall for HTTP:**

# Linux (UFW)
sudo ufw allow 80/tcp

# Windows PowerShell
New-NetFirewallRule -DisplayName "HTTP" -Direction Inbound -Protocol TCP -LocalPort 80 -Action Allow

2. Configure HTTPS Server (Port 443)

Set up secure HTTPS with SSL/TLS:

**Generate Self-Signed Certificate:**

# Linux - Generate certificate
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 \
  -keyout /etc/ssl/private/apache-selfsigned.key \
  -out /etc/ssl/certs/apache-selfsigned.crt

# Enable SSL module
sudo a2enmod ssl
sudo systemctl restart apache2

**Configure Apache for HTTPS:**

# Edit SSL virtual host
sudo nano /etc/apache2/sites-available/default-ssl.conf

# Enable site
sudo a2ensite default-ssl
sudo systemctl reload apache2

**Verify HTTPS Setup:**

# Check port 443 is open
nmap -p 443 192.168.1.1

# Test SSL connection
openssl s_client -connect 192.168.1.1:443

# Check certificate
curl -kv https://192.168.1.1

3. Configure SNMP Service (Port 161)

Set up SNMP for enumeration practice:

**Linux SNMP Setup:**

# Install SNMP daemon
sudo apt install snmpd snmp

# Configure community strings
sudo nano /etc/snmp/snmpd.conf

# Add these lines:
# rocommunity public
# rwcommunity private

# Restart service
sudo systemctl restart snmpd

**Windows SNMP Setup:** 1. Open Server Manager → Add Features 2. Select SNMP Service 3. Configure community strings in Services → SNMP Service → Properties

**SNMP Enumeration Commands:**

# Basic SNMP walk
snmpwalk -c public -v1 192.168.1.1

# Enumerate system info
snmpwalk -c public -v1 192.168.1.1 1.3.6.1.2.1.1

# Get running processes
snmpwalk -c public -v1 192.168.1.1 1.3.6.1.2.1.25.4.2.1.2

# SNMP check tool
snmp-check 192.168.1.1 -c public

# Brute force community strings
onesixtyone -c /usr/share/seclists/Discovery/SNMP/common-snmp-community-strings.txt 192.168.1.1

4. Configure SMB Service (Port 445)

Set up SMB file shares for enumeration:

**Windows SMB Share:** 1. Create folder to share 2. Right-click → Properties → Sharing → Advanced Sharing 3. Enable sharing and set permissions 4. Configure NTFS permissions

**Linux Samba Setup:**

# Install Samba
sudo apt install samba

# Create share directory
sudo mkdir -p /srv/samba/share
sudo chmod 777 /srv/samba/share

# Configure Samba
sudo nano /etc/samba/smb.conf

# Add share:
# [public]
#    path = /srv/samba/share
#    browsable = yes
#    guest ok = yes
#    read only = no

# Restart service
sudo systemctl restart smbd

**SMB Enumeration Commands:**

# List shares anonymously
smbclient -L //192.168.1.1 -N

# Connect to share
smbclient //192.168.1.1/share -N

# Enumerate with smbmap
smbmap -H 192.168.1.1

# Full enumeration
enum4linux -a 192.168.1.1

# Check for vulnerabilities
nmap --script smb-vuln* 192.168.1.1

5. Analyze Service Logs

Review logs for security analysis:

**HTTP/HTTPS Logs:**

# Apache access log
sudo tail -f /var/log/apache2/access.log

# Apache error log
sudo tail -f /var/log/apache2/error.log

# Windows IIS logs
# Location: C:\inetpub\logs\LogFiles\W3SVC1\

**Parse Log for Credentials:**

# Search for POST requests
grep "POST" /var/log/apache2/access.log

# Extract user agents
awk '{print $12}' /var/log/apache2/access.log | sort | uniq -c

Quick Reference

Essential Ports

| Service | Port | Protocol | |---------|------|----------| | HTTP | 80 | TCP | | HTTPS | 443 | TCP | | SNMP | 161 | UDP | | SMB | 445 | TCP | | NetBIOS | 137-139 | TCP/UDP |

Service Verification Commands

# Check HTTP
curl -I http://target

# Check HTTPS
curl -kI https://target

# Check SNMP
snmpwalk -c public -v1 target

# Check SMB
smbclient -L //target -N

Common Enumeration Tools

| Tool | Purpose | |------|---------| | nmap | Port scanning and scripts | | nikto | Web vulnerability scanning | | snmpwalk | SNMP enumeration | | enum4linux | SMB/NetBIOS enumeration | | smbclient | SMB connection | | gobuster | Directory brute forcing |

Constraints

• Self-signed certificates trigger browser warnings
• SNMP v1/v2c communities transmit in cleartext
• Anonymous SMB access is often disabled by default
• Firewall rules must allow inbound connections
• Lab environments should be