Computer Security Fundamentals by Chuck Easttom Chapter 8 Encryption.
Computer Security Fundamentals by Chuck Easttom Chapter 6 Techniques Used by Hackers.
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Transcript of Computer Security Fundamentals by Chuck Easttom Chapter 6 Techniques Used by Hackers.
Computer Security Fundamentals
by Chuck Easttom
Chapter 6 Techniques Used by Hackers
© 2012 Pearson, Inc. Chapter 6 Techniques Used by Hackers 2
Chapter 6 Objectives
Understand the basic methodology used by hackers
Be familiar with some of the basic tools Understand the hacking mentality
© 2012 Pearson, Inc. Chapter 6 Techniques Used by Hackers 3
Introduction
Basic Terminology Reconnaissance
Passive Scanning
Netcraft.com
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Archive.org
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Port Scanning
NMap
NMAP Flags
-O detects operating system -sP is a ping scan -sT TCP connect scan -sS SYN scan -sF FIN scan -sX XMAS Tree scan -sN NULL scan -sU UDP scan -sO Protocol scan -sA ACK Scan -sW Windows scan -sR RPC scan -sL List/DNS scan -sI Idle scan
-Po Don’t ping
-PT TCP ping
-PS SYN ping
-PI ICMP ping
-PB TCP and ICMP ping
-PM ICMP netmask
-oN Normal output
-oX XML output
-oG Greppable output
-oA all output
-T timing
-T0 paranoid
-T 1 Sneaking
-T 2 Polite
-T 3 Normal
-T 4 Aggressive
-T 5 Insane
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Ping Scan
The ping scan sends a single ICMP echo request from the source to the destination device. A response from an active device returns an ICMP echo reply, unless the IP address is not available on the network or the ICMP protocol is filtered.
© 2012 Pearson, Inc. Chapter 6 Techniques Used by Hackers 8
Connect Scan
Fully connect to the target ip address and port. Does a complete TCP handshake. This is the most reliable but will absolutely be detected.
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Syn Scan
Sends syn (synchronize) requests to the target to gather information about open ports without completing the TCP handshake process. When an open port is identified, the TCP handshake is reset before it can be completed. This technique is sometimes called to as "half open" scanning.
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Fin Scan
Sends a FIN (or finish) packet to target. If that port is not listening, no response. If it is listening an error response is received.
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Enumeration
Sid2User Cheops (Linux only) UserInfo UserDump DumpSec Netcat NBTDump
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Cain and Abel
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SQL Injection
One of the most common attacks Depends on knowledge of SQL Basics are easy Versatile and can do a lot more than many
realize
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What Is SQL? A relational database contains one or more tables
identified each by a name. Tables contain records (rows) with data. For example, the following table is called "users" and
contains data distributed in rows and columns: SQL (Structured Query Language) uses commands like
such as SELECT, UPDATE, DELETE, INSERT, WHERE, and others. Example:SELECT * FROM tblUsers WHERE USERNAME = ‘admin’
© 2012 Pearson, Inc. Chapter 6 Techniques Used by Hackers 15
More on SQL
Web sites are written in some programming language such as PHP, ASP, JSP, ASP.net. Those programming languages have their own syntax (NOT SQL). So programmers put the SQL into their code in strings. So lets say you type your username into a text field called txtUsername and your password into a text field called txtPassword. The code in their program has to put SQL statements into a string and append whatever you entered in those two text fields. It will look something like this:
string sSQLstatement; sSQLstatement = “SELECT * FROM tblUSERS WHERE UserName = ‘ “
+ txtUsername.Text +’” + “ AND Password = ‘” + txtPassword.Text +”’”;
so the string will contain
‘SELECT * FROM tblUSERS WHERE UserName =‘admin’ AND Password = ‘password’’;
However whatever you type in, gets put into the text field.
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SQL Script Injection
Single quote added to password: Add the following to the username box and the password:
' or ‘1' =‘1 OR ' or 'a' ='a Also try password’ or (1=1) Or people try anything' OR 'x'='x or people try password:’1=1- - Try using double quote (") if single quote (') is not working
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What Does This Cause?
Well you would have had
‘SELECT * FROM tblUSERS WHERE UserName =‘admin’ AND Password = ‘password’’;
Instead you have
‘SELECT * FROM tblUSERS WHERE UserName =‘' or ‘1' =‘1
’ AND Password = ‘' or ‘1' =‘1
’’;
So now it says to get all entries from table = tblUsers if the username is ‘’ (blank) OR IF 1 =1. And if password = ‘’ (blank) OR IF 1=1!
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Cross Site Scripting
An attacker injects client-side script into web pages viewed by other users. The term cross-site scripting originally referred to the act of loading the attacked, third-party web application from an unrelated attack site, in a manner that executes a fragment of JavaScript prepared by the attacker in the security context of the targeted domain
Essentially you enter scripts into an area that other users interact with. So that when they go to that part of the site, you have your own script run, rather than the intended Web site functionality. This can include redirecting them.
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OphCrack- How It Works
Download OphCrack and burn the image to a CD.
Put the CD in the target computer and boot through CD.
It boots as Linux, grabs the Windows password file, and then uses cracking tools to crack that file and produces a text file with username and passwords.
You cannot even consider yourself a hacker without this tool in your toolkit.
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