1. Introduction

This tutorial is designed to help you develop an effective Incident Response Plan. An Incident Response Plan is a set of instructions to help IT staff detect, respond to, and recover from network security incidents. These types of plans are necessary for dealing with security breaches, denial of service (DoS) attacks, and other threats that could potentially harm a network.

The goal of this tutorial is to provide you with the knowledge and skills needed to develop and implement your own Incident Response Plan aimed at minimizing the damage from incidents and improving your organization's security posture.

By the end of this tutorial, you will learn:
- What an Incident Response Plan is.
- The importance of having an Incident Response Plan.
- How to develop and implement an effective Incident Response Plan.

Prerequisites: Basic understanding of network security concepts.

2. Step-by-Step Guide

Creating an effective Incident Response plan involves the following steps:

2.1. Preparation
The first phase involves setting up the plan. This includes determining the scope of the plan, identifying the team responsible for managing security incidents, and defining roles and responsibilities. It's important to have a list of contacts who can help during a security incident.

2.2. Identification
The identification phase involves detecting and acknowledging incidents. This involves having a strong monitoring system in place to identify potential security threats.

2.3. Containment
Once an incident has been identified, it needs to be contained to prevent further damage. This involves isolating the affected systems and making a backup for further analysis.

2.4. Eradication
In this phase, the root cause of the incident is identified, and the threat is completely removed from the system.

2.5. Recovery
The recovery phase involves restoring the affected systems back to normal and confirming that no threats remain.

2.6. Lessons Learned
After the incident has been dealt with, it's important to document everything that occurred and what actions were taken. This can help to prevent similar incidents in the future.

3. Code Examples

In most cases, developing an Incident Response Plan won't involve coding, as it is mainly a strategic process. However, here is an example of a Python script that can help to detect changes in your network, which could be a sign of a security incident:

import os
import sys
import hashlib

def md5_hash(filename):
    md5 = hashlib.md5()
    with open(filename, 'rb') as f:
        for chunk in iter(lambda: f.read(4096), b''):
            md5.update(chunk)
    return md5.hexdigest()

def monitor_files(directory):
    hashes = {}
    for filename in os.listdir(directory):
        hashes[filename] = md5_hash(filename)
    return hashes

def detect_changes(directory, hashes):
    for filename in os.listdir(directory):
        if md5_hash(filename) != hashes[filename]:
            print(f'File {filename} has been changed')

hashes = monitor_files(sys.argv[1])
while True:
    detect_changes(sys.argv[1], hashes)

This script monitors a directory for changes by comparing file hashes. If a file's hash changes, it prints a message notifying that the file has been changed.

4. Summary

In this tutorial, we've covered the basics of creating an Incident Response Plan, including preparation, identification, containment, eradication, recovery, and learning from the incident.

For further learning, consider studying different types of security incidents and how they can be handled. Additionally, reading case studies of real-world security incidents can provide valuable insights.

5. Practice Exercises

1. Write a basic Incident Response Plan for a small business.

2. Consider a specific type of security incident (e.g., ransomware attack). How would your response plan change?

3. Review a recent high-profile security incident. What could have been done differently with the benefit of hindsight?

Remember, the most effective response plans are those that are updated regularly with lessons learned from both exercises and real incidents. Always strive to iterate and improve your plan.