Cross site Scripting attack:

OS command execution attack:

SQL injection attack:

Hacking Web Application Exposed:
Chapter 6: Input Validation Attacks
Chapter 7:  Attacking Web Datastores
It is recommended to read the whole book.

Hacking Web 2.0 Exposed
Part I: Attacking Web 2.0 
Common Injection Attacks
Cross-Site Scripting

Interested in Reverse engineering? 
Reversing : Secrets of Reverse Engineering

Reverse Engineering Section at Wikibooks : (Free)

Ok, so you want to secure your system or..even hack people's systems?
But wait.. Is it possible to secure or hack a system when you know nothing about its internal structure, or at least how it works?
This list will help you to answer that question. However, by no mean this is an exhaustive list.
NOTE: You can find almost all books mentioned in here in our library. (Most of them are online ebooks)

How to become a Hacker:
Excellent article by Eric Raymond - a prominent hacker.
The article discusses what skills / technical knowledge are essential to become a hacker.
Network security researchers and hackers alike will benefit greatly from this article.

Note: The term "Hacker" in here does not necessarily refer to Black-hat Hacker.

Knowing at least one scripting language is essential for any hacker.

Learning Python, 3rd Edition

By: Mark Lutz

Publisher: O'Reilly Media, Inc.

Introductory level book of Python.

Programming Python, Third Edition

By: Mark Lutz

More advanced book.

TCP/IP Illustrated Vol1
by W. Richard Stevens
Classic TCP/IP book.

Practical Packet Analysis, 1st Edition

By: Chris Sanders

Publisher: No Starch Press

This books shows how WireShark has made the process of packet analysis becoming so easy and quick. Little theory, very practical.

Your Unix: The Ultimate Guide 2nd Edition
ISBN-13: 978-0072520422
Basics of Unix/Linux system.

UNIX Shells by Example (3rd Ed.)
by Ellie Quigley . ISBN 0134608666
Practical unix shell.


Programming PHP, 2nd Edition

By: Kevin Tatroe; Rasmus Lerdorf; Peter MacIntyre

Web Database Applications with PHP & MySQL, 2nd Edition
by Hugh E. Williams, David Lane . ISBN: 0596005431

MySQL™: The definitive guide to using, programming, and administering MySQL 4.1 and 5.0, Third Edition
By: Paul DuBois

Head First SQL

By: Lynn Beighley

Publisher: O'Reilly Media, Inc.

From HeadFirst Team: Head First SQL has a visually rich format designed for the way your brain works, not a text-heavy approach that puts you to sleep.

Head First JavaScript
By: Michael Morrison
Publisher: O'Reilly Media, Inc.
ISBN-10: 0-596-52774-8

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