Frequently Used Cyber Crimes
Unauthorized access to computer systems
or networks
This activity is commonly referred to
as hacking. The Indian law has however given a different connotation
to the term hacking, so we will not use the term "unauthorized
access" interchangeably with the term "hacking".
Theft of information contained in electronic
form
This includes information stored in
computer hard disks, removable storage media etc.
Email bombing
Email bombing refers to sending a large number
of emails to the victim resulting in the victim's email account (in
case of an individual) or mail servers (in case of a company or an
email service provider) crashing. In one case, a foreigner who had
been residing in Simla, India for almost thirty years wanted to
avail of a scheme introduced by the Simla Housing Board to buy land
at lower rates. When he made an application it was rejected on the
grounds that the 169 schemes was available only for citizens of
India. He decided to take his revenge. Consequently he sent
thousands of mails to the Simla Housing Board and repeatedly kept
sending e-mails till their servers crashed.
Data diddling
This kind of an attack involves
altering raw data just before it is processed by a computer and then
changing it back after the processing is completed. Electricity
Boards in India have been victims to data diddling programs inserted
when private parties were computerizing their systems.
Salami attacks
These attacks are used for the
commission of financial crimes. The key here is to make the
alteration so insignificant that in a single case it would go
completely unnoticed. E.g. a bank employee inserts a program, into
the bank's servers, that deducts a small amount of money (say Rs. 5
a month) from the account of every customer. No account holder will
probably notice this unauthorized debit, but the bank employee will
make a sizable amount of money every month.
To cite an example, an employee of a
bank in USA was dismissed from his job. Disgruntled at having been
supposedly mistreated by his employers the man first introduced a
logic bomb into the bank's systems.
Logic bombs are programmes, which are
activated on the occurrence of a particular predefined event. The
logic bomb was programmed to take ten cents from all the accounts in
the bank and put them into the account of the person whose name was
alphabetically the last in the bank's rosters. Then he went and
opened an account in the name of Ziegler. The amount being withdrawn
from each of the accounts in the bank was so insignificant that
neither any of the account holders nor the bank officials noticed
the fault.
It was brought to their notice when a
person by the name of Zygler opened his account in that bank. He was
surprised to find a sizable amount of money being transferred into
his account every Saturday.
Denial of Service
attack
This involves flooding a computer
resource with more requests than it can handle. This causes the
resource (e.g. a web server) to crash thereby denying authorized
users the service offered by the resource. Another variation to a
typical denial of service attack is known as a Distributed Denial of
Service (DDoS) attack wherein the perpetrators are many and are
geographically widespread. It is very difficult to control such
attacks. The attack is initiated by sending excessive demands to the
victim's computer(s), exceeding the limit that the victim's servers
can support and making the servers crash. Denial-of-service attacks
have had an impressive history having, in the past, brought down
websites like Amazon, CNN, Yahoo and eBay!
Virus / worm
attacks
Viruses are programs that attach
themselves to a computer or a file and then circulate themselves to
other files and to other computers on a network. They usually affect
the data on a computer, either by altering or deleting it. Worms,
unlike viruses do not need the host to attach themselves to. They
merely make functional copies of themselves and do this repeatedly
till they eat up all the available space on a computer's memory. 170
The VBS_LOVELETTER virus (better known as the Love Bug or the
ILOVEYOU virus) was reportedly written by a Filipino
undergraduate.
In May 2000, this deadly virus beat the
Melissa virus hollow - it became the world's most prevalent virus.
It struck one in every five personal computers in the world. When
the virus was brought under check the true magnitude of the losses
was incomprehensible. Losses incurred during this virus attack were
pegged at US $ 10 billion.
The original VBS_LOVELETTER utilized
the addresses in Microsoft Outlook and emailed itself to those
addresses. The e-mail, which was sent out, had "ILOVEYOU" in its
subject line. The attachment file was named "LOVE-LETTER-FORYOU.
TXT.vbs". The subject line and those who had some knowledge of
viruses, did not notice the tiny .vbs extension and believed the
file to be a text file conquered people wary of opening e-mail
attachments. The message in the e-mail was "kindly check the
attached LOVELETTER coming from me".
Since the initial outbreak over thirty
variants of the virus have been developed many of them following the
original by just a few weeks. In addition, the Love Bug also uses
the Internet Relay Chat (IRC) for its propagation. It e-mails itself
to users in the same channel as the infected user. Unlike the
Melissa virus this virus does have a destructive effect. Whereas the
Melissa, once installed, merely inserts some text into the affected
documents at a particular instant during the day, VBS_LOVELETTER
first selects certain files and then inserts its own code in lieu of
the original data contained in the file. This way it creates
ever-increasing versions of itself. Probably the world's most famous
worm was the Internet worm let loose on the Internet by Robert
Morris sometime in 1988. The Internet was, then, still in its
developing years and this worm, which affected thousands of
computers, almost brought its development to a complete halt. It
took a team of experts almost three days to get rid of the worm and
in the meantime many of the computers had to be disconnected from
the network.