Transcript System Penetration with Metasploit Framework

System Penetration
with Metasploit Framework
Presentation by Rob Bobek
Content
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Part I:
 System Penetration
 Many Attack Vectors
 Understanding Software Exploitation Attacks
 Understanding Exploits
 Understanding Payloads
 Metasploit Framework
 Understanding MSF
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Part II:
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Snort Introduction
Understanding Snort
Snort Installation/Configuration
IDScenter Configuration
The Attack Experiment
Network Topology and Hardware Configuration/Details
Software Details
Vulnerability Details
Conducting the Attack
Snort Observations
References
Questions
Part I – System Penetration
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What do I mean by System
Penetration?
The act of successfully breaching security on a
remote computer system in order to gain some
form of control access.
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So, what is Metasploit Framework?
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First we need to learn some basic concepts before
understanding what the Metasploit Framework is and what it is
capable of providing.
Many Attack Vectors!
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Gaining access to a secured system can be a difficult task that
requires skill and maybe luck. However, we have also have plenty
of simple techniques, commonly used today, to achieve the same
result. Such include;
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Authentication Attacks
 Password guessing using common strings or using default passwords
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Password Brute Force Attack
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Ex: Wireless Routers have default passwords  Majority don’t change this!!!
Ex: Windows Administrator Account are often blank
These method has become extremely fast with the of Rainbow Tables!
 Rainbow tables pre-computed tables of password hashes.
Social Engineering Attacks
 To influence someone into divulging confidential information using
techniques.
 Ex: Phishing Attacks
 A malicious user who impersonates him or herself as trustworthy
a entity
SQL Injection Attacks
 To inject unexpected malformed SQL into a query in order to manipulate the
database in unintended ways.
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Ex: Injection of SQL to spit out information from certain tables
Ex: Inject an administrator account for yourself
Many Attack Vectors!
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However, one of the most dangerous and yet a
very effective attack used by malicious users today
are Software Exploitation Attacks!
Software Exploitation Attacks can be used to
gain access to unauthorized systems, leverage
user account privileges, crash systems or provide
installation of malicious software (such as
Spyware, Virus’s, Trojans, Adware, etc.) without
the awareness of the other party.
Understanding S.E. Attacks.
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First, let’s understand basics.
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According to Wikipedia;
“The word vulnerability, in computer security, refers to a weakness in a
system allowing an attacker to violate the confidentiality, integrity,
availability, access control, consistency or audit mechanisms of the system
or the data and applications it hosts”
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To Software Developers, a bug is synonymous to a vulnerability.
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Ex: Errors in program’s source code or flawed program design
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Buffer overflows
Memory leaks
Dead locks
Arithmetic overflow
Accessing protected memory (Access Violation)
Understanding S.E. Attacks
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Regardless though which type of software bug we
are speaking of, they are used as the foundation
to form an exploit.
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Therefore, an exploit is a security attack on a
vulnerability.
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In other words (again), an exploit attacking a vulnerability is
generating an event that the application/program/OS is not
programmed/designed to recover successfully and therefore the
result is a system that discontinues to function correctly
How will this give us access to a secured System?
Ans: It won’t.
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Each exploit can be designed to meet the methodology
of your attack.
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Ex: An attacker exploits an IDS to reboot it or crash it
before he/she launches a further attack to avoid detection.
Understanding Payloads
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However, Exploits have more potential!
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They are commonly used to install system
malware or gain system access or recruit client
machines into an existing ‘botnet’.
This is accomplished with the help of a payload
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The payload is a sequence of code that is executed when
the vulnerability is triggered
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To make things clear, an Exploit is really broken up into two
parts, like so;
EXPLOIT = Vulnerability + Payload;
Understanding Payloads
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The payload is usually written in Assembly Language
Platform and OS dependant.
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A Win32 payload will not work in Linux (even if we are
exploiting the same bug)
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Big Endian, Small Endian Architectures
Different payload types exist and they accomplish different
tasks
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exec  Execute a command or program on the remote system
download_exec  Download a file from a URL and execute
upload_exec  Upload a local file and execute
adduser  Add user to system accounts
Understanding Payloads
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However, the most common payload type used with
exploits are shellcodes or aka shell payloads.
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These payloads are very useful because they provide the attacker
an interactive shell that can be used to completely control the
system remotely
The term is inherited from Unix  /bin/sh
For Win OS’s, shells actually refer to command prompt 
cmd.exe
There are two different types of shell payloads;
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Bind Shells  A socket is created, a port is bound to it and when
an a connection is established to it, it will spawn a shell.
Reverse Shells  Instead of creating a listening socket, a
connection is created to a predefined IP and Port and a shell is
then shoveled to the Attacker.
Metasploit Framework
What is the Metasploit Framework?
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According to the Metasploit Team;
“The Metasploit Framework is a platform for writing, testing, and using
exploit code. The primary users of the Framework are professionals
performing penetration testing, shellcode development, and
vulnerability research.”
Understanding MSF
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The MSF is not only an environment for exploit
development but also a platform for launching
exploits on real-world applications. It is packaged
with real exploits that can provide real damage if
not used professionally.
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The fact that MSF is an open-source tool and
provides such a simplified method for launching
dangerous attacks, it has and still is attracting
wannabe hackers and script kiddies that do no
more than create additional problems on networks
and system.
Part II – Snort Introduction
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A
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problem exists will large networks 
Without proper equipment, it becomes more difficult for
Administrators and Analyst's to continuously keep track
of the security and integrity of their network. This is true
because larger network have more potential areas to be
targeted and therefore detection of attacks become a
challenging task.
What are Network Intrusion Detection System’s?
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This is proper equipment
It is technology that has been designed to automatically
detect malicious content on a network and provide the
administrator with a response in the event of a problem.
Understanding Snort
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Simply, Snort is an open-source Intrusion Detection System
(IDS) and an Intrusion Prevention System (IPS) technology.
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Meaning it will monitor our networks traffic for malicious
content to determine if there is a problem and it will also take
immediate action if it detects a problem
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Snort can perform real-time analysis on packet streams to
detect many variations of attacks and probes. Such attacks and
probes include, as listed on snorg.org, are buffer overflows,
stealth port scans, CGI attacks, SMB probes, OS fingerprinting
attempts, and much more.
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Snort is also a real-time alerting agent.
 Example: Snort can be configured to send Bob an e-mail
when a low-priority attack is detected but send Joe a pager
notification when a high-priority attack is detected.
Snort Installation/Configuration
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Installation easy!
 Requires WinPcap libraries
However, configuration is not so easy
 Required manual modifications to snort.conf
 Difficult to debug
IDScenter makes snort configuration much easier!
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http://www.engagesecurity.com/products/idscenter/
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In a nutshell, IDScenter is a front-end GUI for the snort.conf
configuration file
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IDScenter also includes;
 snort.conf testers
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No worries about syntax
Alert file viewer
IDScenter Configurations
Figure: IDScenter Main Panel
IDScenter Configurations
Figure: Initialize Environment Variables
IDScenter Configurations
Figure: Added Bleeding Edge Threats Rulesets
The Attack Experiment
Goal:
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To conduct a Software Exploitation Attack
using Metasploit Framework against a Victim
machine in order to gain system access
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To make things interesting, the Victim’s
machine will also have Snort running locally as
an IDS in order to see how it reacts to the
attack.
Network Topology and Hardware
Configurations/Details
Software Details
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Victim
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(*No anti-virus or similar scanner is running on this machine)
Operating System: Windows XP Professional 5.1.2600,
Service Pack 2 (not fully updated)
Snort 2.7.0
Attacker
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Operating System: Slackware Linux via BackTrack 2
Bootable Live CD
Metasploit Framework 3.0 – Beta Development Release
Vulnerability Details
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Microsoft Security Bulletin - MS06-001
Vulnerability in Graphics Rendering Engine Could
Allow Remote Code Execution (912919)
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Originally posted on January 5, 2006
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However, it was running wild as a 0-Day vulnerability for
a couple weeks
The heart of the vulnerability was within ‘Graphics Rendering
Engine’ of the OS; where a problem would occur whenever it
handled corrupted Windows Metafile images. This is was not
typical buffer overflow problem but merely a flaw in the
design.
At the time, it was an extremely critical vulnerability!
Conducting the Attack
Figure: Booting up Backtrack
Conducting the Attack
Figure: Metasploit Command Line Interface
Conducting the Attack
Figure: Exploit Selection
Figure: Exploit Initialization
Conducting the Attack
Figure: Payload Selection
Conducting the Attack
Figure: Module and Payload Configuration
Conducting the Attack
Figure: Attack launched using ‘exploit’ command
Conducting the Attack
Figure: Victim Exploited
Conducting the Attack
Figure: Successful attack opens remote control session
Figure: Active sessions
Conducting the Attack
Figure: System Access !
Figure: ‘ipconfig’ executed on Victim’s machine
Figure: Attack and the effects of it detected by Snort
References
[1] “Software Bug”
URL: http://en.wikipedia.org/wiki/Computer_bug
[2] “Computer Security”
URL: http://en.wikipedia.org/wiki/Computer_security
[3] “Exploit (computer security)”
URL: http://en.wikipedia.org/wiki/Exploit_(computer_security)
[4] “BackTrack Security Live CD”
URL: http://www.remote-exploit.org/
[5] “Metasploit Framework”
URL: http://www.metasploit.com/
[6] “Snort”
URL: http://www.snort.org/
[7] “WinPcap”
URL: http://www.winpcap.org/
[8] “IDScenter”
URL: http://www.engagesecurity.com/products/idscenter/
[9] ” Bleeding Edge Threats”
URL: http://www.bleedingthreats.net/
[10] “Microsoft Security Bulletin MS06-001”
URL: http://www.microsoft.com/technet/security/bulletin/MS06-001.mspx
Questions ?