8: Basic SecurityNetworking for Home & Small Business

Network Intrusion

• Attacks can be devastating– Cost money, time, theft of

files, etc

• HACKERS– Intruders who gain

access by modifying software or exploiting software vulnerabilities

4 Threats from the Hacker

• Stealing Confidential Info– Credit card #’s– Private Company info such as a project in

development– Could be sold

4 Threats from the Hacker

• Destroy or Alter Records– Send a virus that reformats HD– Changing your grades– Change store prices

4 Threats from the Hacker

• Identity Theft– Stealing info to take on identity– Applying for credit cards & buying stuff– Obtain DL’s

4 Threats from the Hacker

• Disrupting Service– Preventing user from accessing services such

as Internet

Activity

Where’d He Come From?

• External Threat– Outside attacker– Internet or Wireless

Where’d He Come From?

• Internal Threat– Has authorized access

• Knows people & network• Knows what info is valuable

– OR someone may have just picked up a virus

• According to the FBI, internal access and misuse of computers systems account for approximately 70% of reported incidents of security breaches.

Social Engineering

• Deceiving internal users into performing actions or revealing confidential info– Takes advantage of them– Usually don’t meet them face-to-face

Fight Intrusion

• http://www.us-cert.gov/reading_room/before_you_plug_in.html

• http://www.us-cert.gov/reading_room/distributable.html

3 Types of Social Engineering

• Pretexting, Phishing, and Vishing

Phishing

Review

Let’s Try This…

• Cyber Security Awareness Quiz

Other Attacks

• Viruses, Worms and Trojan horses– Malicious software put on hosts– Damage system, destroy data, deny access– They can forward data to thieves– Can replicate to other hosts

3 Evil Things

• Viruses, Worms and Trojan horses– Go to 8.2.1.2

Simplified

Virus Attaches to a program

Can reproduce Causes havoc!

Worm Self-replicating Sends copies of itself to other comp. w/ security holes

Cause harm to network; ties up bandwidth

Trojan Horse

Computer program disguised

Does damage when run

Can’t replicate

Let’s See…

• GCIT

• Who wants to play…– ID Theft Faceoff?– Invasion of the Wireless Hackers?– Phishing Scams?

• Quiz Time for all!– http://www.sonicwall.com/phishing/

Activity

• Virus, Worm or Trojan Horse???

Just Being Evil!

• Sometimes the goal is to shut a network down & disrupt the organization– Can cost a business lots of money!!

Denial of Service (DoS)

• In general, DoS attacks seek to:– Flood a system or network with traffic to

prevent legitimate network traffic from flowing – Disrupt connections between a client and

server to prevent access to a service– Some are not used much anymore, but can be

• SYN flooding

• Ping of Death

DoS- SYN Flooding

DoS- Ping of Death!

• Sending SO MANY pings, the server can’t respond to anyone else!

DDoS

• DDoS– Attack by multiple systems infected with DDoS

code– Sends useless data to server– Overwhelms system & it crashes

Brute Force

• Fast computer used to guess passwords or decipher encryption code

• Brute force attacks can cause a denial of service due to excessive traffic to a specific resource or by locking out user accounts

• Try 8.2.2.3

Review

• Name 3 types of social engineering.– Pretexting, Phishing, Vishing

• How are you targeted in a pretexting attack?– Over the phone

• You click on a pop-up window to claim a “prize.” A program was installed w/out you knowing & now an attacker has access to your system. What is this called?– Trojan Horse

Review

• Which attack doesn’t need activation and copies itself across the network?– Worm

• A server is busy responding to a SYN with an invalid source IP address. What’s the attack?– SYN Flooding

Other Threats

• Not all threats do damage– Some collect info

• Spyware

• Tracking Cookies

• Adware

• Pop-ups

Spyware

• Program that gathers personal info w/out your permission– Info sent to advertisers

• Usually installed unknowingly– Downloaded, installing a

program, click on pop-up

• Can slow computer down or make settings changes

• Can be difficult to remove

Tracking Cookies

• Form of spyware– Not always bad

• Records info about user when they visit web sites– Allows personalization– Many sites require them

Adware

• Form of spyware

• Records info about user when they visit web sites

• For advertising purposes– Pop-ups & pop-ups of ads

Pop-Ups (and Pop-Unders)

• Adware EXCEPT doesn’t collect any info

• Pop-ups– Open in front of the current browser window

• Pop-unders– Open behind the current browser window

What’s This?

Spam

• Unwanted bulk mail from advertisers• Spammer sends

– Often sent through unsecured servers– Can take control of computers– Then sent from that computer to others

• On average, how many spam emails are sent to a person per year?– 3000

Review

• You visit a web site and see this annoying advertising tactic that appears in a new window. What is it?– Pop-up

• This type of advertising is sent to many, many people. The advertiser uses no marketing scheme.– Spam

• This form of spyware is not always bad & can be used for personalization of a site.– Cookies

Security Measures

• You can’t eliminate security breaches– You can minimize the risks

• Policy

• Procedures

• Tools & Applications

Security Policy• Formal statement of rules when using tech

– Acceptable use policy– Detailed handbook

• What should be included?

Activity

• Let’s review some policies…

More Security Procedures

• The procedures help implement the policies

• Some of the security tools and applications used in securing a network include:

Rut Roh!

• Computer starts acting abnormally• Program does not respond to mouse and

keystrokes.• Programs starting or shutting down on their own. • Email program begins sending out large

quantities of email• CPU usage is very high • There are unidentifiable, or a large number of,

processes running. • Computer slows down significantly or crashes

Anti-Virus Software

• Preventive & Reactive tool

• Features– Email checker– Dynamic Scanning (checks files when

accessed)– Scheduled scans– Auto update

• When a virus is known, they will update it

Anti-Spam

• Spam sends unwanted emails– Code takes over PC to send more

• The software ID’s it & places it in junk folder or deletes it

• On PC or on email server– ISP may have a spam filter

Other ways to prevent spam

• Keep anti-virus up to date

• Don’t forward suspect emails

• Ignore the virus warning email

• Report spam to admin to be blocked

• Don’t open attachment from people you don’t know

Anti-Spyware

• Spyware & Adware cause virus-like symptoms– Use computer resources

• This software can detect & delete them

• Pop-Up Blockers

Activity

What’s a firewall?• Resides between two or more networks and

controls the traffic between them as well as helps prevent unauthorized access

• Packet Filtering– Based on IP or MAC addresses

• Application / Web Site Filtering– Based on the application.– Websites can be blocked by URL or keywords

• Stateful Packet Inspection (SPI) – Must be responses from internal host– DoS saver

4 Types of Firewalls

Firewall Placement & DMZ

Firewall & DMZ at home/ Port Forwarding/ Wireless AP internal

• Let’s say you have a web server

• It needs to handle web request while you still protect you internal network

• Create a DMZ with the Linksys

Lab 8.4.2.4??

• Server CD

Is Your Network Vulnerable?

• Tools to help identify where attacks can occur– Number of hosts on a network– The services hosts are offering– The OS and update versions on hosts– Packet filters and firewalls in use

• Lab 8.4.3.2?– Vulnerability Analysis

Lab 8.4.3.2?

• Vulnerability Analysis

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8: Basic SecurityNetworking for Home & Small Business