Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Attacking and Exploiting Modern Web Applications

You're reading from   Attacking and Exploiting Modern Web Applications Discover the mindset, techniques, and tools to perform modern web attacks and exploitation

Arrow left icon
Product type Paperback
Published in Aug 2023
Publisher Packt
ISBN-13 9781801816298
Length 338 pages
Edition 1st Edition
Languages
Arrow right icon
Authors (2):
Arrow left icon
Simone Onofri Simone Onofri
Author Profile Icon Simone Onofri
Simone Onofri
Donato Onofri Donato Onofri
Author Profile Icon Donato Onofri
Donato Onofri
Arrow right icon
View More author details
Toc

Table of Contents (14) Chapters Close

Preface 1. Part 1: Attack Preparation
2. Chapter 1: Mindset and Methodologies FREE CHAPTER 3. Chapter 2: Toolset for Web Attacks and Exploitation 4. Part 2: Evergreen Attacks
5. Chapter 3: Attacking the Authentication Layer – a SAML Use Case 6. Chapter 4: Attacking Internet-Facing Web Applications – SQL Injection and Cross-Site Scripting (XSS) on WordPress 7. Chapter 5: Attacking IoT Devices – Command Injection and Path Traversal 8. Part 3: Novel Attacks
9. Chapter 6: Attacking Electron JavaScript Applications – from Cross-Site Scripting (XSS) to Remote Command Execution (RCE) 10. Chapter 7: Attacking Ethereum Smart Contracts – Reentrancy, Weak Sources of Randomness, and Business Logic 11. Chapter 8: Continuing the Journey of Vulnerability Discovery 12. Index 13. Other Books You May Enjoy

How smart contracts work on the Ethereum blockchain and security considerations

The first thing to understand is what contracts are, how applications using smart contracts are structured, and how they get on the blockchain. We’ll understand the most famous vulnerability, named Reentrancy.

What are smart contracts in the Ethereum blockchain?

To define smart contracts, we can refer directly to the documentation on Ethereum, which states that a smart contract “is simply a program that runs on the Ethereum blockchain. It’s a collection of code (its functions) and data (its state) that resides at a specific address on the Ethereum blockchain.” [8]

Contracts have a balance and can use it, as specified in their functions, such as via fund transfer or state change. You can send transactions that call upon these functions to interact with these contracts.

Smart contracts – being Turing-complete – can be used to develop different things:

...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime