Tutorial Playlist

Cyber Security Tutorial: A Step-by-Step Guide


What is Cybersecurity?

Lesson - 1

Cyber Security for Beginners

Lesson - 2

How to Become a Cybersecurity Engineer?

Lesson - 3

What is Ethical Hacking?

Lesson - 4

What is Penetration Testing?: A Step-by-Step Guide

Lesson - 5

What Is SQL Injection: How to Prevent SQL Injection

Lesson - 6

How to Become an Ethical Hacker?

Lesson - 7

What Is a Firewall and Why Is It Vital?

Lesson - 8

The Complete Know-How on the MD5 Algorithm

Lesson - 9

A Definitive Guide to Learn the SHA 256 Algorithm

Lesson - 10

What Is a Ransomware Attack and How Can You Prevent It?

Lesson - 11

A Look at the Top 5 Programming Languages for Hacking

Lesson - 12

The Most Informative Guide on What Is an IP Address?

Lesson - 13

The Best Ethical Hacking + Cybersecurity Books

Lesson - 14

10 Types of Cyber Attacks You Should Be Aware in 2021

Lesson - 15

The Top Computer Hacks of All Time

Lesson - 16

Top 6 Cyber Security Jobs in 2021

Lesson - 17

The Best Guide to The Top Cybersecurity Interview Questions

Lesson - 18

What Is a Brute Force Attack and How to Protect Our Data Against It?

Lesson - 19

The Top 5 Cybersecurity Skills You Must Have

Lesson - 20

Your Guide to Choose the Best Operating System Between Parrot OS vs. Kali Linux

Lesson - 21

All You Need to Know About Parrot Security OS

Lesson - 22

The Best and Easiest Way to Understand What Is a VPN

Lesson - 23

What Is NMap? A Comprehensive Tutorial for Network Mapping

Lesson - 24

What Is Google Dorking? Your Way to Becoming the Best Google Hacker

Lesson - 25

Your Best Guide to a Successful Cyber Security Career Path

Lesson - 26

The Value of Python in Ethical Hacking and a Password Cracking Tutorial

Lesson - 27

The Best Guide to Understand What Is TCP/IP Model?

Lesson - 28

What Are Keyloggers and Its Effect on Our Devices?

Lesson - 29

Best Guide to Understand the Importance of What Is Subnetting

Lesson - 30

Your Guide to What Is 5G and How It Works

Lesson - 31

How to Crack Passwords and Strengthen Your Credentials Against Brute-Force

Lesson - 32

A Look at ‘What Is Metasploitable’, a Hacker’s Playground Based on Ubuntu Virtual Machines

Lesson - 33

One-Stop Guide to Understanding What Is Distance Vector Routing?

Lesson - 34

Best Walkthrough for Understanding the Networking Commands

Lesson - 35

Best Guide to Understanding the Operation of Stop-and-Wait Protocol

Lesson - 36

The Best Guide to Understanding the Working and Importance of Go-Back-N ARQ Protocol

Lesson - 37

What Are Digital Signatures: A Thorough Guide Into Cryptographic Authentication

Lesson - 38

The Best Spotify Data Analysis Project You Need to Know

Lesson - 39

A One-Stop Solution Guide to Understand Data Structure and Algorithm Complexity

Lesson - 40

Your One-Stop Guide ‘On How Does the Internet Work?’

Lesson - 41

An Introduction to Circuit Switching and Packet Switching

Lesson - 42

One-Stop Guide to Understanding What Is Network Topology?

Lesson - 43

A Deep Dive Into Cross-Site Scripting and Its Significance

Lesson - 44

The Best Walkthrough on What Is DHCP and Its Working

Lesson - 45

A Complete Look at What a Proxy Is, Along With the Working of the Proxy Server

Lesson - 46

A Detailed Guide to Understanding What Identity and Access Management Is

Lesson - 47

The Best Guide to Understanding the Working and Effects of Sliding Window Protocol

Lesson - 48

The Best Guide That You’ll Ever Need to Understand Typescript and Express

Lesson - 49

Express REST API

Lesson - 50

All You Need to Know About Express JS Middleware

Lesson - 51

An Absolute Guide to Know Everything on Expressions in C

Lesson - 52

A Definitive Guide on How to Create a Strong Password

Lesson - 53

Ubuntu vs. Debian: A Look at Beginner Friendly Linux Distribution

Lesson - 54

Your One-Stop Guide to Learn Command Prompt Hacks

Lesson - 55

Best Walkthrough to Understand the Difference Between IPv4 and IPv6

Lesson - 56
The Complete Know-How on the MD5 Algorithm

With the consensus aiming towards an educated public on digital privacy, it’s no surprise to see an increasing interest in encryption algorithms. MD5 algorithm was one of the first hashing algorithms to take the global stage as a successor to the MD4 algorithm. Despite the security vulnerabilities encountered in the future, MD5 remains a crucial part of data infrastructure in a multitude of environments.

Before diving headfirst into the main topic, it is best to go through the basic concept of hashing first.

What is Hashing?

Hashing consists of converting a general string of information into an intricate piece of data. This is done to scramble the data so that it completely transforms the original value, making the hashed value utterly different from the original.


Hashing uses a hash function to convert standard data into an unrecognizable format. These hash functions are a set of mathematical calculations that transform the original information into their hashed values, known as the hash digest or digest in general. The digest size is always the same for a particular hash function like MD5 or SHA1, irrespective of input size.

Hashing has two primary use cases:

  • Password Verification:

It is common to store user credentials of websites in a hashed format to prevent third parties from reading the passwords. Since hash functions always provide the same output for the same input, comparing password hashes is much more private.


The entire process is as follows:

  1. User signs up to the website with a new password
  2. It passes the password through a hash function and stores the digest on the server
  3. When a user tries to log in, they enter the password again
  4. It passes the entered password through the hash function again to generate a digest
  5. If the newly developed digest matches the one on the server, the login is verified

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  • Integrity Verification:

Some files can be checked for data corruption using hash functions. Like the above scenario, hash functions will always give the same output for similar input, irrespective of iteration parameters.


The entire process follows this order:

  1. A user uploads a file on the internet
  2. It also uploads the hash digest along with the file
  3. When a user downloads the file, they recalculate the hash digest
  4. If the digest matches the original hash value, file integrity is maintained

Now that you have a base foundation set in hashing, you can look at the focus for this tutorial, the MD5 algorithm.

What is the MD5 Algorithm?

MD5 (Message Digest Method 5) is a cryptographic hash algorithm used to generate a 128-bit digest from a string of any length. It represents the digests as 32 digit hexadecimal numbers.


Ronald Rivest designed this algorithm in 1991 to provide the means for digital signature verification. Eventually, it was integrated into multiple other frameworks to bolster security indexes.


The digest size is always 128 bits, and thanks to hashing function guidelines, a minor change in the input string generate a drastically different digest. This is essential to prevent similar hash generation as much as possible, also known as a hash collision.

You will now learn the steps that constitute the working of the MD5 algorithm.

Steps in MD5 Algorithm

There are four major sections of the algorithm:

Padding Bits

When you receive the input string, you have to make sure the size is 64 bits short of a multiple of 512. When it comes to padding the bits, you must add one(1) first, followed by zeroes to round out the extra characters. 


Padding Length

You need to add a few more characters to make your final string a multiple of 512. To do so, take the length of the initial input and express it in the form of 64 bits. On combining the two, the final string is ready to be hashed.


Initialize MD Buffer

The entire string is converted into multiple blocks of 512 bits each. You also need to initialize four different buffers, namely A, B, C, and D. These buffers are 32 bits each and are initialized as follows:

A = 01 23 45 67

B = 89 ab cd ef

C = fe dc ba 98

D = 76 54 32 10

Process Each Block

Each 512-bit block gets broken down further into 16 sub-blocks of 32 bits each. There are four rounds of operations, with each round utilizing all the sub-blocks, the buffers, and a constant array value. 

This constant array can be denoted as T[1] -> T[64].

Each of the sub-blocks are denoted as M[0] -> M[15].


According to the image above, you see the values being run for a single buffer A. The correct order is as follows:

  • It passes B, C, and D onto a non-linear process.
  • The result is added with the value present at A.
  • It adds the sub-block value to the result above.
  • Then, it adds the constant value for that particular iteration.
  • There is a circular shift applied to the string.
  • As a final step, it adds the value of B to the string and is stored in buffer A.

The steps mentioned above are run for every buffer and every sub-block. When the last block’s final buffer is complete, you will receive the MD5 digest.

The non-linear process above is different for each round of the sub-block.

Round 1: (b AND c) OR ((NOT b) AND (d))

Round 2: (b AND d) OR (c AND (NOT d))

Round 3: b XOR c XOR d

Round 4: c XOR (b OR (NOT d))

With this, you conclude the working of the MD5 algorithm. You will now see the advantages procured when using this particular hash algorithm.

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Advantages of MD5


  • Easy to Compare: Unlike the latest hash algorithm families, a 32 digit digest is relatively easier to compare when verifying the digests.
  • Storing Passwords: Passwords need not be stored in plaintext format, making them accessible for hackers and malicious actors. When using digests, the database also gets a boost since the size of all hash values will be the same.
  • Low Resource: A relatively low memory footprint is necessary to integrate multiple services into the same framework without a CPU overhead.
  • Integrity Check: You can monitor file corruption by comparing hash values before and after transit. Once the hashes match, file integrity checks are valid, and it avoids data corruption.

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How Can Simplilearn Help You?

The message digest family of algorithms has been a staple in many hashing systems across the globe. They have their flaws, but they can still be considered an excellent beginner algorithm for newer cryptographic enthusiasts. Apart from this particular subject, there are multiple sections in cybersecurity that need to be practiced before one starts a career in this line of work.

Both novices and seasoned professionals can benefit from Simplilearn's "Cybersecurity Expert" course. The course is loaded with activities, live classes, and a solid base to start your career in this lucrative industry, from addressing the basics of cybersecurity to teaching its most complex aspects.


In this lesson regarding the MD5 algorithm, you took a small recap into hashing and its use in today’s industry. You understood the origin of MD5 and learned its process of scrambling the information.

Are there any queries regarding the topic you just learned? If yes, please comment below, and we will be happy to answer them for you. 

About the Author

Shruti MShruti M

Shruti is an engineer and a technophile. She works on several trending technologies. Her hobbies include reading, dancing and learning new languages. Currently, she is learning the Japanese language.

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