Transcript chapter_11modified

Chapter 11: Network and Internet
Privacy and Security
Instructor: <enter your name>
Chapter 11: Network and Internet
Privacy and Security
Learning Objectives:
Understand the basic concepts of computer security
Identify common threats when using a computer on a
network
Identify various malware programs
Recognize the importance of securing personal data
Develop strategies to make a computer more secure
Computers connected via networks and the Internet are
vulnerable to a range of malicious activities. These machines
are at risk for attacks that can cause poor performance or
destroy data, or can cause users to become victims of fraud
or identity theft.
Security Specialist
• have the skills to protect computers and networks.
• are responsible for ensuring that all the security devices in
a company are correctly configured.
• able to spot different types of attacks and know how to
respond to each one.
Computer Security Goals
Computer security is built around upholding three
basic goals:
Confidentiality. Your data should be visible and
accessible only to those whom you choose to see
it.
Integrity. The data you see and store should be
reliable and accurate, and should not be
tampered with.
Availability. Your data should be accessible when
you want it, including after a mishap or disaster.
Phishing
Phony emails and web pages imitate legitimate ones to
trick people into giving away personal information
phishing :The act of attempting to acquire information
such as usernames, passwords, credit card information,
and so forth, by pretending to be from a genuine,
trustworthy source such as a bank.
Identifying phishing:
 Check the source of the email
 Hover the mouse over the hyperlinks to check the URL
being referred to
 Look for grammar and spelling mistakes
 Check for a security padlock icon in the address bar of the
browser
Remember: Real companies and banks never ask for
personal information online
Example Phishing Message
Example: Phishing Website
Spoofing
Attacker’s computer assumes a false IP address
Attacker waits for a legitimate user to log in, and
then hijacks that user’s IP address and takes over
Packet Sniffing
Captures data packets as they travel across the
network and decodes their content
Content may be useless to the criminal, or may
contain credit cards numbers, user names, or
passwords
Captures data packets as they travel across the
network and decodes their content
Content may be useless to the criminal, or may
contain credit cards numbers, user names, or
passwords
Password Cracking
password cracking: The act of attempting to identify a user’s
password in order to gain access to a system or program.
Password cracking can be accomplished in several ways:
Guessing
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Dictionary words
Proper names
Using information the hacker knows about the victim
Social engineering: tricking or befriending the person to get
personal information
Keylogger
 Malware that records every keystroke of the computer
being hacked
 These keystrokes include user names and passwords
Social Engineering
 The art of obtaining someone’s password either by
befriending her or tricking her into sharing it.
Password cracking software
Malware
Computer criminals engage in a wide variety of activities to
compromise computer system, data, and online identity. They
are aided in their efforts by various types of harmful malicious
software, Grouped together under the title malware.
Virus: A type of malware that is installed without the
user’s knowledge or consent, that attaches to an
executable file, spreads to data, other programs and
executable files or even to the boot sector of the hard
drive when the program is run.
The most common way for a virus to spread is for a
user to open an infected email attachment or Internet
link without having virus protection in place.
Malware
Worm: Travels over a network, rather than attaching to
specific files, often spreads via email. The
consequences of worms range from destructive to
annoying. A worm might delete files or direct users to a
fake website, or it might just do something annoying
like swapping left and right mouse button actions.
worm will consume most of network bandwidth.
Trojan: Pretends to be a useful program to get the user
to run it. May install spyware or adware or cause other
harm
Spyware: A type of malware that Spies on the user’s
computer habits, including recording user names and
passwords and reports them back to the spyware’s
developer or to a third party, which uses it to target the
user with pop-up advertisements—often for fake
products.
Adware: Pops up unwanted ads
Example of Trojan
Ransomware
Ransomware: A type of Trojan that encrypts files on a user’s
system. It then displays a message describing how to decrypt the
files which inevitably involves sending payment over the Internet.
Even after the money is sent, however, the files are not decrypted.
Antivirus Software
Detects and removes viruses, worms, Trojans, and
sometimes more complex threats and other malware.
Requires regular updates for the latest threats
Deletes or quarantines infected files. Examples are
Symantec, Sophos, Kaspersky, McAfee , Microsoft ‘s
Security Essentials, AVG etc. are among the most
popular.
DoS Attacks and Zombies
Denial of Service (DoS): Attacker floods a site with
thousands of requests for access, blocking legitimate
requests.
A coordinated attack (many thousands of computers from all
over the world) in which the target website or service is
flooded with requests for access, to the point that it
cannot deal with them all. As a result, legitimate users
are prevented from accessing the site or service.
Zombie: A computer that launches a DoS attack
Computers become zombies after being infected by a
bot (a type of Trojan)
Botnet: A network of zombie computers infected with
bots, often numbering in the thousands. Computer
criminals use botnets to conduct DoS attacks.
Rogue Wi-Fi
Rogue Wi-Fi: a Wi-Fi network that tries
to intercept and spy on user traffic.
A wireless network that “sniffs” traffic,
making a copy of everything users type
including usernames, passwords, credit
card numbers etc.
Rogue networks may be present in
public places like airports which
doesn’t need a password.
Insecure networks are identified with a
small exclamation mark; the other
networks have encrypted connections.
Unsuspecting users may log into the
rogue network instead of the
legitimate one for that facility
Wireless Network Security
Encryption Types
 Wired Equivalent Privacy (WEP) 64-bit or 128-bit
encryption, older technology
 Wi-Fi Protected Access (WPA): 128-bit encryption
 WPA2: Improved version of WPA with 128-bit or 256-bit
encryption
Wi-Fi Protected Setup (WPS)
 Push a button on one device and then click a button on the
other device to connect them without having to use the
encryption key
Service Set ID (SSID)
 The router/switch name; don’t broadcast it for greater
security
Data Privacy Laws
To protect people’s privacy, there are rules to govern how personal
information is handled. Most countries have data protection and
privacy laws to control the access and distribution of this personal
information. These laws are needed to regulate the companies that
hold our personal information and to ensure that all our information
is properly protected.
Most countries have laws that ensure that digital data
about a person is:
◾ Used only for the intended purpose
◾ Accurate
◾ Sufficient for the purpose, with no unnecessary
information held
◾ Accessible by the owner
◾ Obtained legally
◾ Kept secure from unauthorized access
◾ Deleted when no longer needed
Social Networking Privacy Risks
Oversharing of personal information on social networks.
Employers or potential employers checking your
personal account.
Criminals targeting your home while you are on
vacation.
some of the “friends” you make online may not be who
they say they are.
Cyberbullying: what starts as a fun activity, interacting
with friends online—turns ugly. Someone makes
unpleasant comments about you online . Others join the
conversation . People might even post rumors or altered
images of you in an attempt to harass you . This is called
cyberbullying—and it’s a growing problem .
Cookies
Small text files that websites place on your hard drive containing data to
use in your next session with that website
Stored in your user settings folder by default.
For example, some cookies contain personal information that a hacker could use to
gain access to a website while pretending to be you. The hacker could then use your
PayPal or credit card information in a fraudulent manner, for example. Or, a hacker
could trick you into downloading a Trojan that steals your cookies and sends them to
the hacker’s computer, enabling him to use them at will.
To prevent, you can delete cookies.
Passwords
What can you password-protect?
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BIOS Setup
Operating system
A data file (in some applications)
Login for a website
Strong passwords
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Long (at least 8 characters)
Combination of upper and lower case
Includes digits and symbols
Not a dictionary word
Not a proper noun
Locking the Computer
You can lock your computer in one of two ways .
1. Press the Ctrl+Alt+Del keys at the same time . You will be
presented with an options screen; select the Lock This
Computer option to lock the computer .
2. Alternatively, press the Windows+L keys at the same time . To
unlock the computer, simply enter your system password, as
shown here .
Windows + L keys
Ctrl+Alt+Delete and then click Lock Computer
Folder Sharing Permission
If your Windows computer will have more than one regular user,
you can create a user account for each person. Each user can
choose to share some of his folders with other users on the
computer, without granting access to all the data in his account.
You can also share folders and files with other users over a
network. This is done through the use of permissions.
Firewall
Firewall: Security barrier that controls what traffic is
allowed to be sent and received on your computer
Applies preset rules that you can configure to
determine which traffic is blocked
Prevents outside hackers from entering your computer
on unused ports
Windows comes with Windows Firewall
Windows
Firewall
Encrypting Data
Encrypt: To scramble the contents of a file so it cannot
be read without the required permission to decrypt it.
Decrypt: To reverse the encryption of a file so that
the file appears in its original form again.
Encrypting File System (EFS)
 Encryption in Windows on an NTFS volume
 Scrambles data; can only be unscrambled by an authorized
computer or user
 Set it up from the Security tab in the folder’s Properties
box
Bitlocker
 Whole-drive encryption, in some versions of Windows
 Prevents drive from being read if removed from current
computer
Encrypting Internet Communications
In addition to encrypting your hard drive and the individual files on it,
some websites enable you to encrypt your Internet communications.
To determine whether an Internet connection is secure,
check to see whether the URL starts with https rather than http or
look for a padlock icon in the web browser’s address bar.
(The padlock icon appears to the right of the URL in Internet Explorer and to
the left in Firefox, as shown here.)
Both indicate a secure connection between your computer and the
website; data captured between these two points will be
Unreadable.
Preventing Data Loss
Backup utilities (e.g. Backup utility in Windows)
Online backup services
Manually copying files to backup locations
Operating System Updates
Automatically downloaded and installed by
default
Major updates are called Service Packs
Windows Update
Configured from the Control Panel
Wiping Old Drives
Remove data from an old hard drive before
disposing of or recycling it
Simple deletion may not be enough; drive content
can still be reconstructed
Use a drive-wiping utility for better security
Example of a Drive-Wiping
Application
Key Terms
bot
botnet
cookie
cyberbullying
database
decryption
denial of service
(DoS) attack
encryption
firewall
keylogger
malware
password cracking
phishing
ransomware
rogue Wi-Fi
service pack
service set
identification
(SSID)
sniffing
social engineering
social network
spoofing
spyware
Trojan
virus
Wi-Fi Protected
Access (WPA)
Wi-Fi Protected
Setup (WPS)
Windows Update
Wired Equivalent
Privacy (WEP)
worm
WPA2
zombie
Summary
1 . List four types of activities that computer
criminals engage in.
2 . Why is it important to have an active firewall
either on your computer or at the edge of your
network (or both)?
3 . How many different types of threats can be
detected by security solution software products?
4 . Why do you need to be careful when using Wi-Fi
in public places?
5 . Why is sniffing a threat?
6 . What are the effects of a denial of service attack?