Transcript Document

Hacking and its Defense
GROUP MEMBERS
Chan Li
Suman Lohani
Prabhu Sundaram
Objective
Why this topic??
Surprising Facts on Hacking –
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U.S. Department of Defense is attacked some 250,000
times each year
- Source: The Business Journal
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A Microsoft-operated site was cracked and defaced
Monday by someone calling himself “flipz.” It was the first time
a Microsoft Web site has been breached successfully.
- Dated: oct 26 Source: abc.com
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Worldwide cost of the Code Red computer worms that
were unleashed on the Internet in July and August has reached
about $2.6 billion U.S. ($1.1 billion in clean-up costs and $1.5
billion in lost productivity)
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- Source: www.ns2000.org
 Estimated total cost for 2001
$15 billion
Love Bug - $8.7 billion
Melissa- $1.2 billion
 Explorer-$1 billion
 SirCam- $1.035 billion
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 Finally, www would have been radically
different if there were no Hackers.
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Cost of virus attacks on information systems
around the world
 2000 - $17.1 billion
 1999 - $12.1 billion
Here, we will Discuss the practice of
hacking in general and demonstrate a few of
the current common methods, exploits and
Preventions….
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Reasons to hack !!
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Curiosity
Fame
Belief in open systems
Revenge
Notoriety/Fame
Profit ($$$ or other gain)
Revolutionary
Glossary
 Hacking – 2 definitions
1. Hobby/Profession of working with computers.
2. Hacking refers to acts of unauthorized access or
intrusion, in a computer, network, or telecom
system by means of computer device, gadget and or
softwares. –
often referred to as the 2nd one who refer cyber
criminals as “Crackers”
 PhreakingThe art and Science of Cracking the Phone Network
(for eg: free long- distance calls). By extension, security –
cracking especially communication networks.
 Back-Door ProgramA feature programmers often build into programs to
allow special privileges normally denied to users of the
program. Often programmers build back doors so they
can fix bugs. If hackers or others learn about a back
door, the feature may pose a security risk.
Glossary
 Smurfing
- Popular hacking technique by which attackers can persuade
your network to perform a denial of service attack on a machine
somewhere else on the Internet. Such attacks can also generate large
quantities of traffic on your network…
Prevention: use a line: no ip directed-broadcast
 Spoofing
A common technique used to attack sites is to create TCP/IP
packets which appear to be from local IP addresses.
Prevention: The site router is in an ideal place to detect
and prevent these attacks, since it can detect when packets with
internal source addresses arrive on the external interface of the
router…
Glossary
 Trojan Horse Program
A program which may be planted on your hard drive
by an email message attachment, and may be designed to send
information about your system back to the hackers which wrote it.
 Spy Ware
A program which you have downloaded from a legitimate
company, but which—unbeknownst to you—has been written to
track your every move on the internet for marketing purposes and
send the information back to the company.
Glossary
 Denial of Service
An attack specifically designed to prevent the normal
functioning of a system and thereby to prevent lawful access to
the system by authorized users.
Hackers can cause denial of service attacks by destroying or
modifying data or by overloading the system's servers until
service to authorized users is delayed or prevented.
 Sniffing
The use of a sniffer to capture passwords as they cross
a network. The network could be a local area network, or the
Internet itself. The sniffer can be hardware or software.
Glossary
 Virus - Vital Information Resources Under Siege
A computer virus is a specific type of malicious computer
code that replicates itself or inserts copies or new versions of itself
in other programs.
 Worm
Worms are parasitic computer programs that replicate, but
unlike viruses, do not infect other computer program files. Worms
can create copies on the same computer, or can send the copies to
other computers via a network
Damages likely be Caused !!
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Stealing or destroying data
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Disabling protection systems
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Shutting down entire networks
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Disclosure of Information, such as
theft of credit card numbers
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Denial of service attacks including
Smurfing…
A common methodology is the
following
 1. Gather target information.
 2. Identify services offered by target to the public
(whether intentional or not).
 3. Research the discovered services for known
vulnerabilities.
 4. Attempt to exploit the services.
 5. Utilize exploited services to gain additional
privileges from the target.
Reiterate steps 1-5 until goals are achieved.
Steps Hackers generally follow !!
Step 1: Gather target information..
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Domain names, IP address ranges
InterNIC contact information
Physical addresses
Organizational structures
Alliances and financial information
Names of officers, managers, technical staff
Newsgroup posts
Step 2: Indentify services !!
 Web Servers
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FTP Servers
DNS Servers
e-mail gateways
Help desks/phone support
other (gopher, LDAP, irc, etc.)
Step 3: Research vulnerabilities
 Vendor announcements.
 Default configurations.
 Poor configurations. (ie. Passwords, cleartext
protocols)
 Gather available exploits or develop new exploit
 Derived exploits
 Some original work.
Step 4: Exploit Vulnerabilities.
 Attempt to exploit vulnerabilities to gain access to the target.
 Continue until Successful.
Step 5: Utilize increased access
 Exploit additional vulnerabilities to gain additional access and
information to use in penetrating further into an organization.
 The hacker "becomes" a legitimate user (even an
administrator).
Demo on IIS Web Exploit !!
 Only requires normal web user access to an IIS webserver
(i.e. port 80 or 443).
 Using non-standard ports for your web server only makes
this marginally more difficult. You do publish how to access
your webserver to someone, right? (also, you would be
surprised what search engines contain about you.)
 Using SSL (https protocol) will not prevent the exploit
from succeeding.
Demo : Software Levels
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Target: Windows NT Server 4.0sp6a, IIS 4.0
 Attacker: Linux 2.2.17-21mdk kernel, Window NT
Worstation 4.0 sp6a
Demo : Target info
 Target IP address is 192.168.168.125
 Query whois database at ARIN.net to locate owner and
domain information.
 Also try reverse DNS mappings for host/domain names.
Demo : Services information
Use nmap to scan target for services of interest.
$ nmap -sS -p 21-25,80,135-139,443 192.168.168.125
Starting nmap V. 2.53 by [email protected] (
www.insecure.org/nmap/ )
Interesting ports on (192.168.168.125):
(The 7 ports scanned but not shown below are in state: closed)
Port
State
Service
21/tcp open
ftp
80/tcp open
http
135/tcp open
loc-srv
139/tcp open
netbios-ssn
443/tcp open
https
Nmap run completed -- 1 IP address (1 host up) scanned in 1 second
Demo: Research services
Use netcat or telnet commands to determine web server information.
$ nc 198.168.168.125 80
HEAD / HTTP/1.0
<CR>
HTTP/1.1 200 OK
Server: Microsoft-IIS/4.0
Content-Location: http://192.168.168.125/Default.htm
Date: Mon, 06 Aug 2001 23:40:10 GMT
Content-Type: text/html
Accept-Ranges: bytes
Last-Modified: Mon, 30 Jul 2001 15:28:47 GMT
ETag: "c0bf6c53c19c11:b50"
Content-Length: 4325
Demo : Exploit services to gain access
 Unicode “dot dot” exploit to traverse filesystem
 Default configuration of Inetpub\scripts directory is
used to upload and execute commands of our choice.
 Get target to fetch useful commands.
 Get target to initiate a command session.
 Use target to obtain additional information.
Prevention on IIS
 Stay current on patch levels for Microsoft's OS
and web server.
 Implement good firewalling.
 Use an IDS system (or two!).
 Host security is important (Microsoft's "Securing
IIS” and “Securing Windows NT” documents).
 Pattern matching intercept proxies.
Demonstration
 Ping, ifconfig, tracert(Icmp)
Hacking tools
 IP – tools.exe
 Wotweb.exe
 Superscan.exe
Prevention
 The
Price of a New Web Server $ 800
 The Price of the Application Firewall $ 2500
Having to tell your boss that you’ve
Just been Hacked!!
PRICELESS!!
Some Defense Arsenals for
Computer Security !!
1.
2.
3.
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Password Protection
AntiVirus Software
Encryption
Audit Trails
Smart Cards and Biometrics
Firewalls
Here we will focus about Firewalls…
Firewall
Firewall
H/W firewall
Router/internet
gateways
S/W firewall
Application
Packet
Proxy
filtering
Firewall
firewall
(Squid: -Microsoft proxy server) (ipchains:-Linux)
Proxy Server Example
There are two types of Firewall.
1. Dual Homed
2. Demilitarized Setup.
Dual Homed (Secure Network)
Internet
Router
Firewall +
router +DHCP
Server
Comp Comp Comp
Hub
Comp Comp Comp
Comp
Internet
Firewall
Web Server
mail
Demilitarized Setup
(More Secure
Network)
DNS
Firewall
Database Server
mail
DNS
Firewall Example 1
Firewall Example 2
Firewall Products
 Some Firewall Providers:
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McAFEE ASAP
Trend Micro
Zone Alarm..
Single user- Cost $ 40 (for 1 year)
50 users - Cost $1500
 Some Versions of it are Free to download…..
Useful security related links !!
 SANS Institute (www.sans.org)
 Security Focus Archives (www.securityfocus.com)
 Snort IDS home (www.snort.org)
 Security archives (archives.neohapsis.com)
 CERT Coordination Center (www.cert.org)
 http://www.courses.dsu.edu/ infs750
 www.insecure.org
Mailing Lists
 Risks Digest (www.risks.org)
 BUGTRAQ
(www.securityfocus.com/bugtraq/archive)
 NTBugtraq (www.ntbugtraq.com)
 Win2KSecurity Advice (www.ntsecurity.net)
Securing Web servers
 Apache project (www.apache.org)
http://httpd.apache.org/docs/misc/tutorials.html
 support.microsoft.com
"Resources for Securing Internet Information Services”, Article
ID Q282060.
Conclusion
 How to prevent becoming a target?
!! The only reliable solution to reduce the risk of a
successful intrusion attempt is staying current with
your security infrastructure. This is an ongoing
dynamic process. !!
Areas to be explored includes
 More about Hackers
 SSL, L2TP, Proxy servers (security devices and
software)
 More on Server Vulnerabilities