Which of the following refers to policies procedures and technical measures used to prevent unauthorized access to information systems?

System Vulnerability and Abuse

When data are stored in digital form, they are more vulnerable than when they exist in manual form.

Security refers to the policies, procedures, and technical measures used to prevent unauthorized access, alteration, theft, or physical damage to information systems.

Controls consist of all the methods, policies, and organizational procedures that ensure the safety of the organization's assets; the accuracy and reliability of its accounting records; and operational adherence to management standards.

Threats to computerized information systems include hardware and software failure; user errors; physical disasters such as fire or power failure; theft of data, services, and equipment; unauthorized use of data; and telecommunications disruptions. On-line systems and telecommunications are especially vulnerable because data and files can be immediately and directly accessed through computer terminals or at points in the telecommunications network.

Figure 8-1

FIGURE 8-1 CONTEMPORARY SECURITY CHALLENGES AND VULNERABILITIES The architecture of a Web-based application typically includes a Web client, a server, and corporate information systems linked to databases. Each of these components presents security challenges and vulnerabilities. Floods, fires, power failures, and other electrical problems can cause disruptions at any point in the network.

Wireless networks are even more vulnerable because radio frequency bands are easy to scan. LANs that use the Wi-Fi (802.11b) standard can be easily penetrated by outsiders with laptops, wireless cards, external antennae, and freeware hacking software. Service set identifiers (SSID) identifying access points in a Wi-Fi network are broadcast multiple times and can be picked up fairly easily by sniffer programs. In war driving, eavesdroppers drive by buildings or park outside and try to intercept wireless network traffic. The initial security standard developed for Wi-Fi, called Wired Equivalent Privacy (WEP), is not very effective. WEP is built into all standard 802.11 products, but users must turn it on, and many neglect to do so, leaving many access points unprotected.

Figure 8-2

FIGURE 8-2 WI-FI SECURITY CHALLENGES Many Wi-Fi networks can be penetrated easily by intruders using sniffer programs to obtain an address to access the resources of a network without authorization.

Worms are independent computer programs that copy themselves to computers over a network independently from other computer programs or files, and therefore spread more rapidly. A Trojan horse is an apparently benign program that actually performs some hidden action such as installing malicious code or compromising the security of a computer.

Spyware can also act as malicious software by obtaining information about users' buying habits and infringing on privacy. Keyloggers record keystrokes made on a computer to discover steal serial numbers for software and passwords.

A hacker is an individual who intends to gain unauthorized access to a computer system. The term cracker is typically used for hackers with criminal intent. Hackers spoof, or misrepresent themselves, by using fake e-mail addresses or masquerading as someone else. Hacker activities include:

• Theft of goods and services
• System damage
• Cybervandalism: The intentional disruption, defacement, or even destruction of a Web site or corporate information system.
• Spoofing: Hiding of the hackers true identities or email addresses, or redirecting a Web link to a different web site that benefits the hacker.
• Theft of proprietary information: A sniffer is an eavesdropping program that monitors network information and can enable hackers to steal proprietary information transmitting over the network.
  Denial of service (DoS) attacks: Flooding a network or server with thousands of false communications to crash or disrupt the network. A distributed denial-of-service (DDoS) attack uses hundreds or even thousands of computers to inundate and overwhelm the network from numerous launch points. Hackers can infect thousands of unsuspecting users' computers with malicious software to form a botnet of resources for launching a DDoS.

FIGURE 8-3 WORLDWIDE DAMAGE FROM DIGITAL ATTACKS This chart shows estimates of the average annual worldwide damage from hacking, malware, and spam since 1999. These data are based on figures from mi2G and the authors.

Other examples of computer crime include:

• Identity theft: In identity theft, an impostor obtains key pieces of personal information to impersonate someone else and obtain credit, merchandise, or false credentials.
• Phishing: Setting up fake Web sites or sending e-mail messages that appear legitimate in order to coerce users for confidential data. Other phishing techniques include evil twins (wireless networks masquerading as legitimate Internet hotspots, used to capture personal information) and pharming, redirecting users bogus Web sites posing as legitimate Web sites.

The U.S. Congress responded to the threat of computer crime in 1986 with the Computer Fraud and Abuse Act. This act makes it illegal to access a computer system without authorization. Most U.S. states and European nations have similar legislation. Congress also passed the National Information Infrastructure Protection Act in 1996 to make virus distribution and hacker attacks to disable Web sites federal crimes.

One concern is that terrorists or foreign intelligence services could exploit network or Internet vulnerabilities to commit cyberterrorism or cyberwarfare and cripple networks controlling essential services such as electrical grids and air traffic control systems.

The largest financial threats to businesses actually come from insiders, either through theft and hacking or through lack of knowledge. Malicious intruders may sometimes trick employees into revealing passwords and network access data through social engineering. Employees can also introduce faulty data or improperly process data.

Software errors are also a threat to information systems and cause untold losses in productivity. Hidden bugs or program code defects, unintentionally overlooked by programmers working with thousands of line of programming code, can cause performance issues and security vulnerabilities. Software vendors create lines of code called patches to repair flaws without disrupting the software's operation.

Which of the following refers to policies procedures and technical measures used to prevent unauthorized access?

Which of the following focuses primarily on the technical issues of keeping systems up and running?

Are methods policies and organizational procedures that ensure the safety of the organization's assets?

Is malware that hijacks a user's computer and demands payment in return for giving back access?