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E-Commerce and E-Business



                          11.1   Cyber Security

                          Individuals and groups engage in crime by utilizing the tools provided by Internet for the benefit of
                          people. It is extremely difficult to trace the criminals, and even when they are traced it is difficult to
                          prosecute the culprits due to lack of laws. The governments are gradually trying to regulate the Internet
                          through cyber laws. Law enforcement agencies are given the power to intercept online communications
                          to curb cybercrime.


                                           The Regulation of Investigatory Powers  Act in  Britain gives law enforcement
                                           agencies the power to intercept online communications. South Korea has blocked
                                           access to gambling sites and Singapore has blocked access to pornography sites.

                          11.1.1   Cyber Attacks
                          A cyber threat is an  intended or unintended illegal activity that could lead to unpredictable,
                          unintended, and adverse consequences on a cyberspace resource. Cyber attacks are classified as
                          network based and executable based attacks. Executable based attack happens when a program is
                          executed on a target computer system through either of the following ways:
                          1.  Trojan: Trojan is a computer program with hidden and potentially malicious functions that evade
                              security mechanisms.  They exploit authorizations of a  system entity that invokes  the program.
                              Trojans pretend to do one thing while actually they do something different. Modifying a normal
                              program to perform fraudulent activities in addition to its usual function is known as a Trojan
                              horse attack.  An attacker accesses the  source code of an editor program, modifies it to steal
                              someone’s files,  compiles it  and saves it in the victim’s computer. The next time the victim
                              executes the editor program, the intruder’s  version gets executed.  The editor apart from
                              performing its normal functions transmits the victim’s files to the attacker.

                                           Dmsetup.exe and LOVE-LETTER-FOR-YOU.TXT.vbs are examples of Trojan
                                           programs.
                          2.  Virus: Virus attaches itself to a legitimate program with the intention of infecting other files. A
                              virus cannot run by itself. It requires a host program to get executed and to make it active. It is
                              hidden by nature and propagates by infecting a copy of itself into another program. A virus writer
                              first produces a new useful program, often a game, which contains the virus code hidden in it. The
                              game is then distributed to unsuspecting victims through the available networks. When the victim
                              starts the game program, it examines all the binary programs on the hard disk to see if they are
                              already infected. When an un-infected program is found, the virus program infects it by attaching
                              the virus code to the end of the file and  makes the first instruction jump to the virus code. In
                              addition to infecting other programs a virus can also erase and modify files.


                                            Polyboot.Band AntiEXE are boot viruses.



                                      Virus Creates Cyber Threat

                             Caselet
                           A programmer was accused of unleashing a computer virus named Melissa from a  stolen AOL
                           account. The programmer constructed the virus to evade anti-virus software and to infect computers
                           using           Microsoft Windows and Word programs. The virus appeared on thousands of e-mail
                           systems on March  26, 1999 disguised as an important message from a colleague or friend. The virus
                           was designed to send an infected e-mail to the first 50 e-mail addresses on the address book of the
                           users’ Microsoft Outlook. Each infected computer would send out e-mails to 50 additional computers
                           which in turn would infect                                                Contd…




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