null User manual

null  User manual
Muhammad Tashfeen Shinwari
Cyber Criminology
The Mentality, Vision and Aim behind Cybercrime
Helsinki Metropolia University of Applied Sciences
Bachelor of Engineering
Information Technology
12 December 2015
Muhammad Tashfeen Shinwari
Cyber Criminology The Mentality, Vision and Aim behind Cybercrime
Number of Pages
51 pages
12 December 2015
Bachelor of Engineering
Degree Programme
Information Technology
Specialisation option
Software Engineering and IT security
Kimmo Sauren, Senior Lecturer
The goal of the project is to gain a good understanding of what kind of different cyberattacks are carried out in modern times and how by being cautious, one can avoid becoming a victim. This study will also shed some light on what mentality lies behind these attacks and what the most common intensions are for these types of attacks.
The economic effect of computer crime is often overlooked. Only by knowing some fundamental principles, one can better prepare oneself against these crimes and also protect
personal assets from these threats.
The project is also aimed to give some useful guidelines which can be benefited from not
only by users who are using computers for their daily lives but also by nontechnical people
in general. Nowadays more and more tasks are dependent upon computers and keeping
up with the security issues on the Internet cannot only save people from losing data on a
personal level but also help companies protect their assets.
Different printed and electronic media were used in order to gather the facts and figures
about cybercrime. A few software were also used to mimic some of the attacks on my personal network in order to gain in depth information.
The findings in the thesis indicate that there exists no perfect protection against cyber
threats. However, many of the cyber-attacks that are mentioned in the thesis are carried
out successfully because a normal computer user lacks the necessary information regarding computer security.
Computer user, not only on a personal level but also on an organizational level, should be
trained to adopt safety measures against cybercrime. Also, the end point user awareness
should be encouraged as it can be the strongest defence against such cyber-attacks.
cyber attack, hackers, viruses, malware, security
1 Introduction
2 Brief History of Cybercrimes
3 Types of Hackers
4 World of Malware
4.1 Computer Viruses
4.2 Worms
4.3 Trojan Horses
4.4 Spyware
4.5 Scareware
5 Network Attacks
5.1 Active Attacks
5.1.1 Denial-of-Service(DoS)
5.1.2 Man-In-The-Middle
5.1.3 Session Replay
5.1.4 Identity Spoofing
5.1.5 Password Based Attacks
5.2 Passive Attacks
5.2.1 Wiretapping
5.2.2 Port Scanner
5.2.3 Idle Scan
6 Database Attacks
6.1 SQL Injection
6.2 Excessive Privilege Abuse
6.3 Privilege Elevation
6.4 Weak User Authentication
6.5 Weak Audit Trail
6.6 Exposure of Backup
7 Tools of the Trade
8 Conclusion
A means of accessing a computer that bypasses security
Black hat hacker
People who illegally exploit vulnerabilities in systems for
personal gains
Illegal activity that uses a computer as a primary means of
Data Integrity
Accuracy and consistency of data without any unauthorised
Conversion of data into cipher text not easily understood by
anyone else except the authorized parties
A network device which restricts access to the network
Grey hat hacker
People who exploit weakness in systems to bring awareness to the owners without any malicious intent
A person who exploits weaknesses in a computer system
Malicious software designed to infect a computer system
SQL injection
An attack which is used to penetrate database systems using unauthorised SQL commands
A program or a code written to be installed illegally on the
system often to cause damage to the system
White hat hacker
Security experts dedicated to expose vulnerabilities and fix
them before malicious hackers can exploit them.
Zero day vulnerability
A security hole in software unknown to the vendor
Hypertext Transfer Protocol
Hypertext Transfer Protocol Secure
Intrusion Prevention System
Master Boot Record
Remote Access Trojan
Relational Database Management System
Structured Query Language
Transmission Control Protocol
User Datagram Protocol
Volume Boot Record
Wireless Fidelity
1 Introduction
Technology has a big influence on our daily lives. Electronic devices, computers and
mobile phones have become a necessity. The Internet especially is used as a means
of communication with the rest of the world. It has become a tool not only for communication but also for sharing information, shopping, socializing and many more activities.
Like many other inventions, the Internet has its drawbacks such as scamming, stealing,
user privacy issues, blackmailing and spamming. These drawbacks are used by the
hackers as a source of amusement and also as means of income. In order to overcome
these issues, and make the Internet a safer place, there is a constant battle in the
community. On the one side are the security firms and on the other, the hackers. Security firms try to provide protection against hackers while on the other hand the hackers
try to infiltrate the security measures and compromise computer systems by exploiting
these vulnerabilities.
Computer viruses, worms, Trojan horses and many other such tools are used by the
attackers to carry out crimes. Organizations are spending billions of dollars every year
to protect themselves against such threats. Day by day these attacks are getting more
and more sophisticated so people need to be up to date on security policies in order to
be less vulnerable on the Internet. Modern malicious programs are harder to detect and
can easily infect computers because like security firms, there are professional criminal
organizations spending a great deal of money to invent new ways and techniques to
compromise the systems.
The purpose of this project is to educate computer users about attackers, their ways of
targeting people/computer systems and of ways of preparing a computer user against
the attacks that can change their lives forever. While some solutions can be easily implemented and are well-known practices, computer users and many organizations still
disregard them and solely rely on their antivirus programs to protect them against all
the possible cyber-attacks. While antiviruses are good practise, they are nowhere near
providing a complete secured system. It is up to the users to make small changes in
their working habits. Although it might seem as an extra effort at the time, it can save
them from all problems that lie ahead if proper measures are not taken.
2 Brief History of Cybercrime
Cybercrime started out as hackers tried to gain illegal access to computers either for
the purpose of thrill or for accessing sensitive and classified information. Eventually the
hackers started using viruses for phishing scams and credit card thefts on both personal and business levels.
In the early 1970‟s a computerized phone system became a target. John Draper, a
computer programmer and a phone phreak, figured out the correct codes and tones to
make a free long distance call [1].
In January 1986, the first computer virus called Brain was released. It was a virus for
MS-DOS and infected the boot sector of storage media [2]. The viruses between the
1980‟s and the early 1990‟s were only spreading on floppy disks and these viruses
would jump from one PC to another only by physically moving the floppy disk between
the computers. However, most of these early viruses such as Brain, Stoned, Cascade
and Form were not written for any benefitting purposes. Many of them were created as
a joke e.g. V-sign, Walker and ELVIRA viruses, which would display an animation on
the victim‟s display to let him/her know that the PC had been infected. They did not
cause damage to PCs unlike the Michelangelo virus in 1992 which would override
everything on the victim‟s hard drive on a certain date and was considered a destructive virus [3].
Later in the 1990‟s, the computer viruses became more advanced. In 1995 came viruses which would not infect the floppy disks or the program files but the user documents.
The Concept virus (Macro virus) was the first of its kind which would affect the word
documents, meaning every time the victim would share a word file with someone else,
the virus would be shared as well [4].
Another well-known example is the Happy99 virus, which is the first email virus in history. It would greet its victim happy new year 1999 and then email itself further. Then
came the viruses which were a combination of the Macro virus and the email virus e.g.
the Melissa virus, which would infect a word document and then forward the infected
file to other people on the victim‟s address book [5].
In 2003, Fizzer virus gained popularity as it was the first of its kind of virus that was
written in order to actively make money by taking over the infected computers and use
them to send spams. Other viruses at the time were for example, Sobig, Mydoom
(email worm), Bagel (email worm), Netsky, SDBot, Cabir (the world‟s first mobile
phone virus) and Storm worm [6].
Stuxnet, a computer worm, discovered in June 2010 is looked upon as a game changer in the history of cyber-attacks. It is one of the most sophisticated malware and the
first case of cyber sabotage ever seen [7].
From the years 1980‟s to the year 2015, malware have advanced and are becoming
more sophisticated day by day. Nowadays, it is almost impossible to detect some malware and many of the malware are being detected to have zero day vulnerabilities. In
other words, hackers have managed to find security holes in the software, unknown to
the vendor of that software. Security experts are on a constant battle against these
cyber criminals, trying to make the internet a safer place for all of its users.
3 Types of Hackers
The word hacker has a different meaning for different people. Usually the definition
affiliated with the term hacker is a person who secretly gets access to a computer system in order to gain some sensitive information and causes damage to/through the
system. However, it is important to understand that not all hackers have criminal intentions. There are hackers who are working day and night just to keep a user‟s sensitive
and personal information safe and protect the irreplaceable data that can be priceless
to the user.
One needs to be aware of which hackers can be trusted and which hackers can be the
cause of a distress. Listed below are a few types of hackers that might have an effect
on a user‟s life and should be distinguished.
White Hat Hackers are security experts who are responsible for making sure that a
company‟s and its client‟s sensitive data is secure and out of the reach of the people
who can use that information illegally for personal gains. These IT professionals are
fighting daily against the threats of the hackers called Black Hat Hackers.
Black Hat Hackers are actually the cyber criminals and one needs to be aware of
them. The term hacker is mostly used to refer to black hat hackers. Black hat hackers
are professionals who are highly trained and qualified to carry out cyber-attacks against
the community. They are responsible for breaking into computer systems/networks and
creating computer viruses in order to meet some set goals. Mostly their intensions are
financial benefits. However, their goals vary from trying to make some money by stealing a person‟s credit card information to company espionage and even to government
Grey Hat Hackers also referred to as crackers. They are IT professionals who possess
skills of a black hat hacker but use those skills for good purposes. They try to exploit
vulnerabilities in the system and fix them before black hat hackers could get to them
and take advantage of them.
Script Kiddies are amateur hackers trying to make names for them. They use borrowed programs to hack into weak computer systems/networks and websites. However, the mentality behind such attacks is not financial benefits but a little fame for themselves.
Hacktivists are motivated to hack into systems for political, religious and other social
purposes. Their intensions are not to make money but to expose their targets for better
or worse.
Cyber Terrorists are by far the most dangerous of all hackers and are highly trained
with a wide range of skills and goals. Usually their goals are to disrupt the critical infrastructures for religious or political beliefs.
4 World of Malware
The word malware stands for “Malicious Software”. It is a collective term for viruses,
worms and Trojans that get installed on the victim‟s computer without his/her consent.
They can be used for a wide range of purposes, from crashing victims devices to monitoring and controlling their online activities. Malware are used by cyber criminals to
steal personal information, commit frauds and send spams. Over time, malware have
become more sophisticated and harder to detect. A few of the most basic malware are
explained below.
4.1 Computer Viruses
“A Computer Virus is a small program designed to cause some kind of damage in the
infected computer, by deleting data, capturing information, or by altering the normal
operation of the machine”[9].
A computer virus does not spread on its own. It needs human interaction in order to
spread and causing destruction. A computer virus can range from being slightly
disturbing to causing a total destruction. Depending upon its purpose and ways how it
is transferred from one PC to another, computer viruses can be broadly divided into
three categories.
Boot Virus or a boot sector virus, also known as a memory virus, is most commonly
spread using physical media e.g. through an infected floppy disk or a USB drive. This
virus stays in the boot sector of the floppy and in the Master Boot Record (MBR) of
hard disks. The MBR is responsible for selecting which Volume Boot Record (VBR) to
load based on the instructions or the user input. A boot virus will run itself before the
operating system is loaded [10]. A typical operation of the boot sector virus is shown in
figure 1.
Figure 1. Operation of a boot sector virus [10]
Figure 1 illustrates that the boot sector virus is installed in the boot sector of the computer system. Once the user starts the system, the virus prevents it from running the
default operations i.e. loading the operating system and runs its own instructions and
causes damage to the system. It also transfers itself to any removable disk and infects
the computers on which the disk has been used. Boot viruses are very difficult to detect
and the victim very often does not know about their existence unless he or she runs a
virus scan. However, the boot sector virus will not infect the computer if the virus is
introduced after the boot-up or when the computer is already running the operating
system. The most common examples of boot sector viruses are Brain virus, Polyboot.B virus and Mebroot rootkit [11]. In order to avoid being effected by a boot sector
virus, it is advised to continuously update the antivirus protection program and preferably choose antiviruses that have a large list of boot virus definitions in the registration. If
all the efforts of removing the virus result in vain, the hard drive may need a reformatting in order to get rid of the infection.
Macro Viruses are the most commonly used viruses that exist as macros (scripts) that
run automatically by certain macro-capable programs to infect and duplicate the documents. These viruses are generally made for Microsoft Office and exist in word processing documents and spreadsheets e.g. Concept Virus and Melissa Virus [12]. A
user can realize the existence of a virus e.g. if the computer is running more slowly
than normally or if a user is prompted for a password on a file which does not need a
password or if the documents are saved as template files. There are various ways how
a user can avoid getting effected by such viruses. One safe way is to use a digital signature. These signatures will confirm if the file is coming from the source (the author) or
if it is a tempered file. Of course updating the security virus program will also help in
providing a better protection for the system.
Program Viruses infect executable program files usually with extensions “.BIN”,
“.COM”, “.EXE”, “.OVL”, “.DRV (driver)” and “.SYS (device driver)”. These programs
are loaded in the memory during execution, along with the virus. Usually the program
viruses hide themselves under the name of other legitimate programs and the victim,
thinking that he/she is installing a particular program, is deceived and a malicious program in installed instead. A common example of such viruses are Sunday Virus and
Cascade Virus.
A good practice is to avoid running any executable files, which are from unknown
sources and check the certificates before running any file. It is also advised to create a
system restore point before installing any new program because even if the malicious
program compromises the system, the user could choose to go back to the settings
before the installation of the program. On Windows machines, one should always install windows updates in order to patch the vulnerabilities.
4.2 Worms
Worms are very often mistaken for viruses. However, unlike viruses, worms do not require any human interaction and are more dangerous than viruses. An infected computer, rather than sending out a single worm, can send hundreds and thousands of
computer worms causing devastating damages to society.
Computer worms are self-replicating malicious codes that spread across computers
which are vulnerable and infect them. They do that by attacking the computer network
and then spread to the computers which have weak security policies. They are
responsible for causing harm to systems from deleting files to forwarding them by
emails and by consuming bandwidth to installing backdoors in the computer system. A
backdoor is a means of accessing the computer system by bypassing the security
mechanism. Worms can also open TCP ports in order to create a network security hole
for the other applications to take advantage.
A particularly notorious incident occurred in 1988 when a computer worm named the
Morris worm was created by Robert Tappan Morris. A copy of the Morris code is
shown below in figure 2.
Figure 2. Example of the Morris code [13]
It is argued that the Morris worm was released either accidently or prematurely. The
Morris worm was not written for destructive purposes and it only caused the computer
to slow down because of all the unnecessary processing caused by it [13]. However, it
infected 6000 university, military and research center computers and caused hundreds
of thousands of dollars‟ worth of damage [14]. The worm was designed to be undetectable but due to a design flaw, it made far more copies of itself than initially anticipated
by the developer.
A series of measures should be considered in order to ensure a worm free system.
Scanning any suspicious files with a good antivirus program helps accomplish that
goal. Keeping the antivirus up to date and performing a periodic scan is also recommended.
4.3 Trojan horses
Trojan horses are malicious computer programs that can perform actions on the victim‟s computer without their consent. Even though Trojan horses cannot self-replicate
as viruses and worms, they can cause as much damage to computer systems. There
are a number of actions that a Trojan horse can perform on the victim‟s computer, including blocking data, modifying data, deleting data, copying data or even disrupting
the performance of the computer system/network.
The Trojan horse is generally the malicious code that is hidden inside a safe legitimate
program. In some cases, Trojan horses are spread deceiving the user into believing
that they are programs that will remove viruses from the computer but when run by the
victim, they instead become installed and allow the hacker to get control of the victim‟s
computer. Trojan horses can be subcategorized according to the actions they perform
on the victim‟s computer. Out of many, a few types are the following.
Backdoor (Remote Access Trojans) also known as Remote Access Trojan (RAT),
allows the hacker to remotely control the infected computer. Very often, backdoor Trojans are used to unite a group of infected computers and form a botnet/zombie network, which is then used for criminal purposes by hackers.
Destructive Trojans at times are used just for the purpose of causing inconvenience
to the victim. They also help to make some financial benefits for the hacker in the process. E.g. Ransom Trojan can encrypt a user file in a way that the owner of the file is
no longer able to access the file. Upon receiving the ransom, the hacker promises to
restore the file or the computer system to its normal behavior. An example of one ransomware is shown in figure 3.
Figure 3. An example of Ransomware [15]
Figure 3 is one of many examples of ransomware where the personal files of a user are
encrypted and the user is not allowed to access the files unless he or she pays the
attacker to decrypt his/her files. Another common ransomware which I myself have
come across is called the Poliisi virus. The Poliisi virus can be distributed through several means. Malicious websites or a legit website that has been hacked can infect the
victim‟s machine by exploiting the vulnerabilities in the system. It can also be sent as
an email attachment and upon opening, can infect the system. A screenshot of the Poliisi virus is shown in figure 4.
Figure 4. Poliisi Virus screenshot [16]
This ransomware locks the screen of the computer and does not allow the user to access his/her computer and displays a message with a demand to pay 100€ to unlock
the machine. It uses a bogus message in order to scare its victim into paying. It also
has the ability to access the victim‟s webcam. Even though there are different ways
found on the Internet to get rid of this ransomware, users are advised to avoid opening
attachments or links from unknown senders and avoid visiting websites that look fishy.
Another example of destructive Trojans is the security software disabler, where the
Trojan takes out as many security programs as it can and leaves the victim unprotected
and vulnerable for the next attack.
Proxy Trojans allow the hacker to use the infected computer as a proxy server. It provides the hacker with the possibility of committing frauds such as stealing credit card
information or even to launch malicious attacks against other networks using the infect
4.4 Spyware
Spyware are computer programs that gather user information of the infected PC and
send that information through the Internet to the hacker. Spyware are most commonly
spread bundled with some free programs which are available online.
Spyware are similar to Trojan horses as they are installed unwittingly by the user while
trying to install something else. Once installed on the computer, spyware can monitor
keystrokes, read cookies, snoop chat programs or scan files on the hard drive and
send the information back to the hacker. The information collected is then used by the
hacker either for advertising or for selling it to the third parties.
A common example is the Elf Bowling game introduced in the 1990‟s. It was packed
with a spyware which reported the user information to its developer [17]. Another example is CoolWebSearch (CWS) spyware. This spyware was introduced in May 2003
and it infected the Windows Operating system. Once installed on the PC, it would
change the browser‟s homepage to as shown below in
figure 5.
Figure 5. Example of CoolWebSearch homepage [18]
Coolwebsearch spyware had the capability of creating pop-up ads that would redirect
the user to other websites, collect sensitive and private information of the user and
would also slowdown the infected computer.
A number of anti-spyware programs are available on the Internet e.g. Spybot and Malwarebytes, which are worth buying. Some other commonly used programs as antispware include Webroot Spy Sweeper and eTrust Pest Patrol. Users should be careful
while opening emails from unknown sources and should try to stay away from illreputed websites. A good firewall should also be used in order to hide a user‟s PC from
attackers who would try to access the system through the Internet.
4.5 Scareware
Scareware, also known as smitfraud or rogue security software, is designed to trick its
victims into buying or downloading potentially dangerous software. It displays a message on a pop-up screen such as infected files have been found on the system and the
user must click to remove those files. However, when a user clicks on the screen, unwittingly the malware can be installed on the computer. At times the software asks the
user to buy a program to remove those viruses and that program not only causes the
user to lose money but also contains real malware. A common example is shown below in figure 6
Figure 6. An example of the pop-up screen of scareware [19]
Figure 6 illustrates a typical scareware example where the screen pops up appearing
as if it was from the antivirus installed on the computer. However, in reality it is just
scareware and will either install malware on the computer or will ask the user to purchase a program and then install the malicious program, thus infecting the computer.
A totally secure system is hard to accomplish, but in order to be best protected, the
system should be updated for patches. Programs like Adobe reader, flash player and
Java should be updated with the latest releases as many times as these programs are
used to compromise a system.
5 Network Attacks
Over the passage of time, hackers have learned ways of compromising not just a
single computer but an entire network using one infected computer. Therefore, network
security is a fundamental component while designing a network. A network security
defines the user privileges of what a user can and cannot do with the network
component and resources. Therefore, it is of utmost importance to be aware of the
security threats that might compromise the entire network because of one
compromised system. In the unlikely event of an attack, a system must limit the
damages and should be able to recover as quickly as possible.
Network attacks are very common nowadays and based on the type, they can be
classified into two wide categories, active attacks and passive attacks. A typical
operation of both types of attacks is shown in figure 7.
Figure 7. Active and passive attacks in practice [20]
As shown in figure 7, passive attacks only monitor the network traffic whereas active
attacks try to modify the data sent through the network.
5.1 Active attacks
An active attack is a network exploit where the hacker attempts to modify the data on
the target computer or modify it while it is on the way to the target computer. This
requires the attacker to be able to transmit data to one or both parties. An attacker can
be located in between the talking parties and can stop all or parts of the communication
depending upon his or her intensions. If there are no integrity checks on the system,
the system will not realize that the data has been tempered. These attacks can be
carried out through viruses, worms or Trojan horses. Active attacks are subcategorised
below, based upon the type of action they perform.
5.1.1 Denial of Service (DoS)
Denial of service, or Distributed denial of Service (DDoS), is one of the most common
attacks when it comes to network attacks. This kind of attack is target-specific. It is an
attempt to make a network resource unavailable to its intended users and is done by
flooding the network with useless traffic until to the point where the network shuts down
because of the overload. An example of how an attacker would overflow the resources
is shown below in figure 8.
Figure 8. Anatomy of DDoS attack [21]
The figure illustrates how an attacker uses zoombie computers to flood the network
traffic and the server resources such that the legitimate users can no longer use the
services they are entitled to, and as a consequence the network shuts down due to the
traffic overflow.
Although DoS attacks do not cause any theft of information, they can cost the victim a
great deal of time and money. For example a DoS attack could force a website or a
server to shut down causing the service providers to be unable to provide services to
the entitled customers/users.
While there are no easy tricks to fight against this kind of attack, it is worth using some
simple practises to ensure a safer environment. Computers within a network should be
secured and in case of any malicious activities, they should be cut off from the rest of
the network. Since any computer system can be used for performing a DoS attack, the
most effective solution is a global cooperation effort to ensure a secured Internet.
System administrators should understand the vulnerabilities of their system and should
try to fix them and take proper backups just in case there is a breach in the system.
5.1.2 Man-In-The-Middle (MITM)
A man-in-the-middle attack is a kind of eavesdropping cyber-attack where the attacker
secretly gets access to communication between the two parties and can record,
change or send information that never existed to the parties, pretending the information
was sent from the other communication party. This kind of attack breaks the integrity of
the messages being sent between the two parties. An example of an MITM is shown
below in figure 9.
Figure 9. An illustration of MITM attack [22]
As the figure illustrates, the attacker inserts him/herself in the communication between
the two parties and instead of messages sent directly from one party to another, they
go through the attacker and the attacker forwards the altered or his/her own message
to the reciever party without the parties acknowledging that the message has been
altered. For example, if a buyer purchases an item and the communication between the
buyer and the seller is compromised, an attacker could modify the item amount or the
shipping address for the item causing trouble both for the buyer and the seller.
Prevention against MITM attack is either on the server side or on the routers. Strong
encryption methods can be used between the two parties in which case the communication parties can be identified by their digital certificates. Any mismatch would be a
sign of tempered data. Another method of preventing an MITM attack is to avoid using
open WiFi routers directly. There are various cryptographic algorithms that are available to protect the users from this type of attack.
5.1.3 Replay Attack
When a user logs into a website, to identify the user and the privileges that the user
has, user is assigned a session id which serves as his/her identity. In a replay attack,
an attacker steals the user‟s login information by stealing the session id. The attacker
then has the same rights as the authorised user on the website.
In networks, this attack is used to maliciously delay or repeat the data transmission
without authorization. An authorized user of the network transmits some messages but
the attacker records those messages and can send the same messages at a different
time without knowing the passwords and the keys. This could have bad consequences
such as redundent orders of the purchased items.
An example of the replay attack is shown in figure 10.
Figure 10. Example of a Replay Attack [23]
In the example, Bob and Alice play the role of two friends who want to transfer a
message between themselves. Darth on the other hand plays the role of an attacker.
Bob tries to send a message to Alice but Darth intercepts the message and later sends
the message to Alice and makes it appear as if Bob just sent a message to Alice.
One approach to possibly avoid this kind of attack is that Bob can add a timestamp to
the message so that it could indicate the time when the message was sent and if the
timestamps do not match, it is an indication that there was a third party involved in the
5.1.4 Identity Spoofing
Identity spoofing also known as masquerading, is an attack where the attacker
pretends to be a particular authorized user in order to gain more privileges. After a
successful attack, the attacker compromises the system and use it for his/her own
good. It can be attempted through the use of stolen passwords, finding security loops in
the system or by bypassing the security mechanism. An attacker can trick the victims
into reveiling their passwords or sensitive personal information.
Another type of spoofing attack is the email spoofing where the attacker disguises as
someone else usually as a person the victim might know or might be interested in
knowing. For example, an attacker could send someone a malicious link by email and
try to deceive the receipient into thinking that the email was sent by their friends or
family members or by someone they know. This allows the attacker to gain trust of the
victim and as soon as the victim clicks the link, without his/her knowledge, the system
is compromised.
5.1.5 Password Based Attacks
Passwords are secret words used for the authentication of an identity. While many
users still choose some simple words in order to remember their passwords easily, e.g.
their date of birth or their pet‟s name, using a secure password which is hard to guess
can actually help them to be less vulnerable to these kind of attacks.
When an attacker hacks a user‟s account by hacking his/her password, he/she gains
access to the same rights as the user and if the account hacked has the administrator
rights, it means that the attacker has full control over the system and can perform
actions on the system according to his/her liking.
Different approaches are used by hackers in order to compromise a user account. One
of the most common types is password guessing. Attackers use both a manual and an
automatic approach to guess user passwords. The easiest targets and the most
vulnerable users in this case are the ones who have an easy to guess or a commonly
used password e.g. 1234 or “password”.
Another type of password attack is the dictionary attack where the attacker uses all the
words found in the dictionary to check if there is a match and see if he/she gets access
to a system. Dictionary attacks work because many users and organizations still use
simple words as their passwords in order to avoid the complexity of creating a strong
password and then remembering it.
Sometimes attackers also use password resetting programs in order to avoid the hasle
of guessing passwords. This approach is useful only when an attacker just wants to get
access to a system. However, resetting a password invites undesired attention and that
is the reason attackers prefer password crackers by using password hashes and
converting them into plain text formats instead of password resetters [24].
Password hashing is a process where a clear text which is used as a password is
changed to give completely different values by applying some algorithm on it. This
helps to protect a user from a dictionary-based attack as the password has been
changed to some non-normal value instead of some plain words found in a dictionary.
While one can never garuntee a 100% secure password, using complex and strong
passwords is always recommended as it reduces the chances of being compromised.
As a general strong password, it is recommended to use 8-character long passwords
along with some numbers and special characters in order to maximize security and
minimize the chances of being compromised [25].
5.2 Passive Attacks
Unline an active attack, a passive attack is a network attack where the target system is
monitored and scanned for vulnerabilities. The purpose of this kind of attack is to
gather information about the victim‟s system without changing any data on it. Since
passive attacks do not make any changes to the system or the data on it, they are very
difficult to detect. Based on the intention, passive attacks are further divided into
different categories.
5.2.1 Wiretapping
The history of wire tapping goes back to the days of telegraph when it was first used by
the law enforcement in the New York City in the 1890‟s [26]. At that time, it was used
by FBI, NSA and even business owners to monitor the activities of criminals, terorrists
and office employees [27]. However, due to the advancements in techonology, the term
wiretapping no longer stands for monitoring telephone calls only but is a term also used
for the surveilance of the Internet communication. The term is still used even if no
physical wire is used for the communication between two parties. While passive
wiretapping does not involve modification of the data being transferred, it poses a big
threat to the confidentialiy of communication.
A common tool used for wiretapping nowadays is called a Packet Sniffer. Everything
done on the Internet, e.g. checking emails, browsing the Internet, chatting or
transferring files, the data is always converted into packets. A packet sniffer can
legitimately or illegally monitor the data packets sent over a network. Packet sniffers
help administrators of the network to monitor the network traffic and see bottlenecks if
any. However, the same tool can be used by attackers to analyze the network traffic
and to use that information for destructive purposes. One of the most commonly used
tools for packet sniffing is Wireshark which captures the data packages which can later
be viewed in detail as shown below in figure 11.
Figure 11. Capturing packet data using wireshark [28]
The figure shows a TCP packet selected for viewing. Wireshark is used as a tool for
this purpose as it shows the time, name of each packet, source ip address, the
destination ip address and more information in order to maximize the efficiency of a
network. However, if used by wrong people, it can cause harm.
It is recommended that every network administrator knows how to use these tools in
order to make sure that the network is not compromised in any way and the information
of the clients is securely handled.
From a user‟s point of view, it is important to use HTTPS websites only, instead of
HTTP, because HTTPS uses encryption algorithms, meaning that both the sending
party and the receiving party agree upon a secret “code” and change their documents
into random looking strings. This allows the user‟s information to be securely
transferred over the Internet, thereby reducing the chances of any data breaches.
5.2.2 Port Scanner
Port serves as a communication endpoint in an operating system. It is a point where
the information goes into and out of a system. A port is associated with an ip address
and the type of the protocol used for the communication.There are specific port
numbers defined for different services. HTTP serivce, for example, has a default port
value of 80. A list of a few common port numbers is shown below in figure 11.
Figure 11. Common TCP/UDP port numbers [29]
A port scanner, like the Wireshark, is a tool which is used both by the network
administrators and the hackers for monitoring the network. However, the intensions are
quite different. Network administrators usually use port scanners to verify their network
policies and improve their overall security while the attackers on the other hand try to
use port scanning as a vehicle for reconnoissance, hereby allowing them to gain more
information about the network.
One of the most commonly used tools for a port scanner is called NMap (Network
Mapper). NMap among many other things can scan for open ports in a network and
allow the user to see which ports are currently open in their network and are not being
used for any special tasks at that particular moment. From network administrator‟s
point of view, the open ports which are not being used should be closed as the
attackers try to access the system using those open ports. Figure 12 shows the GUI
(Graphical User Interface) of a network scan where the open ports are listed.
Figure 12. Viewing open ports using NMap [30]
Generally, the idea behind port scanning is to find open ports on a network host. When
a burglar wants to target a house, the first thing he or she looks for is an open door or a
window. The port scanner works in a similar way where the ports act as the doors and
windows of the victims computer. The attacker tries to run a scan and see which ports
on the computer system are open and which can be used to compromise the system.
The attacker might not use those open ports right away but he or she would know an
easy access to the system when he/she would need to break into the system. In some
cases, the attackers can open ports themselves on the target computer in order to get
get access to the system.
Although tools like NMap are freely available on the Internet, network administrators
can actually use these tools to find vulnerabilities in their system and secure their
system from any possible attacks. As a countermeasure for attacks such as port
scanning, the network administrators could define rules in their firewalls, e.g. to look for
malicious behaviour if many ports of their network are being scanned per minute.
Another way to ensure security is to close any unnecessary services on the target
system. In reality all the systems are vulnerable to port scanning. However, the best
offense is a good defense [31]. Network administrators should take a few necessary
steps in order to avoid any catastophic damages in the future.
5.2.3 Idle scan
An idle scan, also known as zoombie scanning, is the stealthiest TCP scanning
technique often used by an attacker. Even though it is another way to scan for open
ports, this technique is used on servers or networks which have strong firewalls, which
makes it very difficult for an attacker to get access to a system. The way this scan
differs from other port scanners is that an attacker can perform this scan on the target
system with his or her own real ip address and still manage to get away with it. This is
done using a zoombie (idle) machine on the network.
Every IP packet on the Internet has a fragment identification number (IP ID). Many
operating systems simply increment this number for each packet being sent, probing
for the IPID can tell an attacker how many packets have been sent since the last probe
[32]. In order for idle scan to work, an attacker first tries to make a connection with the
zoombie computer which is part of the network of the target computer. The attacker
sends a SYN/ACK (Session request acknowledgement) to the zoombie computer. The
zoombie computer not expecting the SYN/ACK, sends back a RST(reset), thereby
disclosing its IPID. Since the zoombie machine is part of the network, it lies within the
trust zone of the target system. The attacker then uses the IP address of this zoombie
computer and sends a SYN (session establishment) packet to the target system. If a
port is open, the target sends back an acknowledgement to the zoombie machine SYN
ACK (session request acknowledgement) or RST(reset) if a port is closed [32]. The
process is shown below in figure 13.
Figure 13. Scanning of an open port [32]
However, when a port is closed and an attacker scans the port, the behaviour is as
follows in figure 14.
Figure 14. Scanning of a closed port [32]
Idle scanning, like port scanning can be easily done using the tool Nmap. After several
bogus requests, network or system administrators might realize that someone is
scanning their network but not only the attacker goes unidentified but also the attacker
manages to map the network.
Luckily there are some defence mechanisms that the administrators can adapt in order
to secure their network from idle scanning. Idle scanning works with zoombie (idle)
machines. In other words, if the machine is not idle and there is communication
between the zoombie machine and the system, idle scanning cannot work. Also when
the attacker tries to use a zoombie machine, he or she is hoping that the zoombie
machine has more rights to the system then they do. A good practise is to not put any
public host in front of the firewall. The firewall should also be able to maintain a stateon connection, meaning that it can determine if someone is making any phony session
requests without a target host response. Also ingress and egress filters can be used on
the network in order to become less easy targets for the attacker [33].
6 Database attacks
Databases are very often a key target for cybercriminals due to the fact that they carry
sensitive and valuable information. Whether that information is private, governmental or
business-related, attackers can always use that information to make some money for
themselves. Usually the more sensitive the information, the more money for cybercriminals. While database attacks are very common, database developers and administrators are said to be responsible for providing such an environment where hackers can
easily breach security and get access to databases [34].
Databases are of utmost importance to many organizations. They are used to store
customer information and other confidential business data. Databases are also the
backbones of many web applications. However, at times due to poor programming
skills and failure to provide strong user validation methods by the web application developers, databases can be compromised.
Many times databases are tested to see if they do what they are supposed to do but
administrators fail to achieve the security aspect, i.e. to check if databases do not do
what they are not supposed to do. Attackers take advantage of these circumstances.
Therefore, safety aspects must be considered from the very beginning phase of an
application using databases, from development to the updating and the maintenance
phases. The next figure 15 graphically shows the data breaches over different periods
of time.
Figure 15. Data breaches from 2006-2015 [35]
Figure 15 graphically represents data breaches from the year 2006 to 2015. The maximum number of data breaches were in 2012 as seen from the figure.
On an average it takes an attacker less than 10 seconds to hack in and out of a database [36]. This is due to this fact that many database attacks go unnoticed until later
when the compromised data has been leaked to the public. According to Noel
Yuhanna, principal analyst with The Forrester Group, “The typical database may have
15,000 to 20,000 connections per second. It‟s not humanly possible to know what all of
these [connections] are doing.” [36]. While it might seem like hackers were using some
complex hacking tools to get access to a database, in reality even nowadays, there
exist so many application vulnerabilities that they can be easily exploited using simple
hacking methods. A few of the database hacking methods most commonly used by
hackers are discussed below.
6.1 SQL injection
SQL stands for Structured Query Language and it is a computer language that is used
to manage data in the RDBMS (Relational Database Management System). An SQL
injection is a database attack where the attacker penetrates the database by using
unauthorised SQL commands. The primary targets of this kind of attack are the
applications or servers which have big backend databases and which carry confidential
and sensitive information. Since this attack can be used against all the databases
which are based on SQL, it is one of the oldest, most prevalent and dangerous of all
attacks. Using an SQL injection, an attacker can take advantage of the vulnerabilities of
an application and use queries to fetch all the usernames and passwords from the
database. This also allows the attacker to see all the data fields in the database and
create, modify and delete the fields if he or she pleases. Over different periods of
times, Sony Pictures, PBS, Microsoft, Yahoo and even CIA have been targets for this
kind of attack. Below figure 16 illustrates an overview of the SQL injection attack.
Figure 16. An example of SQL injection [37]
Hackers use easy tricks to gather information about a database. The easiest way to
notice an SQL injection is to put ' into the input field and if the field is vulnerable to the
SQL injection, an SQL error will be displayed. The hackers actually gather information
using this SQL error. A simple query for the SQL injection is as follows.
SELECT fields FROM aTable
WHERE field = „ $EMAIL‟:
where $EMAIL is the email address which a user provides through a web form. The
attacker does not know the email and instead provides a value
dummy „ OR „1‟=‟1
So the resulting SQL query will be
SELECT fields FROM aTable
WHERE field=‟dummy‟ OR „1‟=‟1‟:
Here 1=1 plays an important role. Since 1=1 is a true statement, the web application is
tricked into displaying every item in the “aTable” field of the database. In the same
manner any other true statement can also be used instead of 1=1 for instance, 9=9 or
a=a. Some common tools used for an SQL injection are Sqlninja, Sqlmap and Paros
There are different vulnerability phases for an SQL injection.
Finding a vulnerability.
Finding out the type and version of SQL server.
Finding out the type of vulnerability.
Resolving the structure of databases.
Stealing or changing information.
Using the stolen information.
Taking control of server and installing backdoors in the server for later use.
Sometimes, a web application is developed properly by taking into account the security
measures. The application does not output any data which normally would be used by
attackers to gain information about the database. In such cases an attacker can use a
Blind SQL injection. A Blind SQL injection is somewhat similar to an SQL injection but
the difference is in the way data is fetched from the database. In a Blind SQL injection,
the attacker asks a series of True or False questions from the database and expects
the database to answer the questions, thereby giving out confidential information to the
attacker. Using a Blind SQL injection to exploit database vulnerability is not easy and
careful reading of the outcomes is needed in order to be able to find the differences
between True and False results.
SQL injections have been around for a while now but still they are a danger that many
big organizations fear. For example, one major SQL injection attack was in March 2008
where Heartland Payment System became the target and 134 million credit cards were
exposed [38].
While SQL injections at times can be hard to detect, there are ways how administrators
can avoid being easy targets for them. Web application developers should possess
good programming skills and be familiar with SQL injection attacks and their consequences. The code that has been written should be reviewed properly keeping security
aspects in mind. Also some automated tools should be used to test the application and
make sure that there are no open vulnerabilities in the system.
The application should use some kind of encryption algorithms in order to store
usernames and passwords, e.g. SHA-1, and avoid storing passwords in plain text form.
Simple security precautionary steps should be taken. If someone tries, for example, to
access the password table, the administrator should be informed by email or by some
other means of communication. The user should not be allowed to enter all characters
into the fields. The user input should be filtered to allow some characters and disallow
certain others.
Another good practise is to create multiple database user accounts instead of one database with each having a minimum level of privilege for their environment. For example, the login page can have a separate database. In that case, even if there is a
breach in the system; the entire database will not be compromised.
Any of the above defences, when applied, can provide better security for a database.
However, as the best practise, all the above techniques should be used at least in order to ensure a safer database.
6.2 Excessive Privilege Abuse
Whenever a user is granted some privileges to use an application, the administrators
should make sure that the user is not given more privileges then he or she requires.
Very often, those privileges are used for malicious purposes. For example, if an office
worker has the administrative rights just because he or she could update the names of
the employees in the database, these rights can also allow him or her to see other personal details of each employee, e.g. salaries and home addresses. According to statistics, excessive privileges have been the top database threat in the year 2015 as shown
in figure 17.
Figure 17. Top ten database threats in 2015 [39]
Abuse of Excessive Privilege is often due to the fact that database developers do not
have extra time to define and maintain access privileges for each user. Consequently,
users are granted some default privileges that might exceed their job requirements.
Large organizations spend a lot of money and effort on protecting themselves from the
outside world but fail to secure themselves from within. It is not unheard of that a rogue
employee of an organization still has access to the system and can cause devastating
loss to the company. Many organizations even nowadays do not have a proper process
for updating user rights.
Attackers have become smarter and faster. They learn the weaknesses of organizations. The attackers understand the fact that in order to compromise an organization‟s
network, illegal access to a computer from within the network, could help to carry out
the attack with less effort and in a time efficient manner. Once the attacker has access
to a computer with excessive or administrative rights from within the network, he or she
can abuse those privileges according to his or her needs. While excessive privilege
attack is not a new concept, many users/organizations even today fail to take the necessary steps in order to avoid these kinds of attacks.
In order to avoid users from having excessive privileges to a database and thus to reduce the chances of an attacker compromising the user account and abusing the user
rights, one solution is query-level access control. The mechanism behind this approach
is that it limits database privileges to the minimum required SQL operations, e.g. SELECT, UPDATE etc. This approach would allow the office worker described in our pre-
vious example, to change the name of the employees in the organization but not to
access any other information. If he or she tries to access some other data fields, an
alert would be generated. Limiting the user privileges can also help to control the damage caused by an attacker when a user account is hacked.
6.3 Privilege Elevation
Sometimes, even if all the privileges are assigned correctly to users by using some
security policies, attackers can manage to change the user rights. Attackers may do
that by taking advantage of the vulnerabilities of the database platform software. These
vulnerabilities might be found in the stored procedures or protocol implementation or
even in SQL statements. An attacker can exploit such vulnerabilities to change a normal user account into an administrator user account.
In order to protect against such an attack, traditional intrusion prevention systems (IPS)
can be used. IPS is often used to identify a known malicious vulnerability in network
traffic. IPS can also be used to block access to all the procedures which are considered
malicious. Unfortunately, IPS alone is not enough to fight against such attacks. Querylevel control should also be used alongside IPS in order to maximize the defence
6.4 Weak User Authentication
Authentication plays a very important role in security. When a user logs into a system,
the username and password are used to confirm the identity of that user and after
being identified, the system assigns the user specific privileges. There are many
different forms of user authentication. A few are mentioned below.
Basic Authentication: Uses cleartext usernames and passwords.
Digest: Mostly the same as basic authentication but the passwords are
Form-based: Uses a custom form and allows the user to enter username and
password which are then verified on the backend during the login process.
Providing fingerprint, using smart cards, voice pattern sample and retinal scan are a
few other methods that are used for user authentication.
Many times people avoiding to learn different and complex passwords, choose some
simple, and easy to remmeber words and even use one password for everything. While
this approach might be convenient, it puts a great danger on the security of the system
and provides the attacker with a welcoming environment.
Some corporations implement effective security mechanisms around their databases,
only to have the rights compromised due to a weak authentication mechanism. In such
environments where passwords are the only defence against attackers, password
strength plays a key role. Instances where default usernames and passwords are used
is a sign of weak user aunthentication.
Originally SQL servers were shipped with a null as default password for the
administrative account “sa” [40]. This information can be easily used by the attacker to
get access to the database server and own it. An attacker can also use social
engineering to hack the password and very often this technique shows promising results. The human nature of trying to be helpful allows attacks like social engineering to
be carried out almost effortlessly. A simple phone call, for example, made by the attacker pretending to be a higher authority can trick people into revealing sensitive information.
In order to protect ourselves from weak authentication attacks, it is recommended to
change the default passwords right away. Strong passwords should be used which are
not easy to guess and should be changed after every fixed period. In order to provide
better security, more than one authentication method should be considered for high
privileged users, e.g. passwords along with retina scan or voice sample or finger prints.
While one can never be too secure, the better security, the less chances of becoming a
6.5 Weak Audit Trail
Weak audit trails can be no less than a terrible nightmare from which it is not easy to
recover for organizations. Many times, in case of a data breach, organizations are not
able to confirm what data has been accessed and who has accessed it.
A weak audit policy exposes the organization to risk on many levels, e.g. regularity
risks, when organizations failing to achieve strong audit trials will often find themselves
at odds with the government regularity requirements. A detection and recovery risk is
also something to consider. When an attacker manages to bypass all the other security
measures, the audit mechanism is the last defense against the attacker, as it will provide the information regarding any violations in the system. Failing to use a strong audit, deprives the organization of the opportunity to detect and/or to report an attack
Databases have the highest rate of breaches among all business assets. A weak audit
lies is in the top five database threat categories. An attacker usually gets away with this
kind of attack because proper system logs are not maintained and once there is a
breach in the system, it cannot be traced back to the attacker. While database developers might argue by stating that taking logs slows down the performance of the system and occupy resources, the attackers are looking for getting their hands on such
In order to protect systems from such attacks, it is important from the very beginning
stage of development that developers understand what data is sensitive and needs to
be protected and monitored. Clear logs should be stored when sensitive data is accessed so that in the case of any data breach, the security team could view the logs
and get a better understanding of the damage done. The logs could be stored on separate systems in order to avoid occupying CPU resources. The audit duties should be
separated from the administrative duties and the rights should be assigned accordingly
so that in the case of a compromised administrator account, the attacker is not able to
delete the log files.
While weak audit attacks are very common, taking some simple precautionary steps
can ensure not only a secure database but also encourage administrators to be more
aware and watch out for attackers.
6.6 Exposure of Backup
While it is a good practise to take backups, in some recent cases backups and stolen
hard drives have been involved in high profile attacks. While organizations spend
millions of dollars trying to protect their data and keeping it secure, sometimes the
security of backup data is overlooked. Stealing backup data is more convenient for
attackers at times than trying to hack the system and gain access to the system. Failing
to monitor the activities of administrators who have access to sensitive information can
also put the data at risk.
Appropriate measures should be taken in order to securely save the backup data and
monitor users who have access to that data. As a good practice it is recommended to
encrypt backup data just in case it gets into the hands of an unauthorized user.
7 Tools of the trade
No matter where computers are being used, either at home or offices, users need to be
educated and they should be aware of all the attacks that are carried out through the
Internet. Users should be aware of any unusual behaviour on their system. Users
should also avoid opening links or files from unknown sources and not share any sensitive information except with authorised personnel.
It is said that the safest computer is the one that is powered off and not connected to
the Internet but that might not be true. Social engineering is a very powerful tool that is
used for tricking users into helping the attacker carry out the attacks. A powered off
computer can be powered on and can be connected to the Internet if a user has no
knowledge regarding security. Such users are easy targets for the attackers. Organizations should educate their employees on security issues no matter if the employee is
working with a computer or not. Many cases are known where an employee, unaware
of the security issues, plugged in a USB drive found in the company‟s premises to the
office PC and infected the system. This approach is used by attackers when they cannot get direct access to a company‟s PCs. Organizations should establish security policies and train their employees accordingly.
While there is no such thing as a fully secured system, there are some great tools
available that would get very close. Antivirus should be installed on all PCs, no matter
if it is a home PC or an office PC. Antivirus should be updated for new virus definitions
and a periodic scan should be run on the entire system. Any plugin device should be
scanned for viruses before opening. Users should not rely solely on the antivirus program, but they should keep an eye on the suspicious behaviour of a file or a program.
Malwarebytes is another good tool that is very often used to detect malware and zero
day threats.
Firewalls play a very important role when it comes to security. Antiviruses detect a malicious program that is already in the computer or is about to be installed, whereas firewall filters the data packets that come into the system and go out. A firewall is well
known to keep hackers out of the network (system) and prevents any unauthorised
Backup of any relevant data is highly encouraged. The backups should be stored possibly with an encryption to protect them in the case of any thefts. Physical security
should also be taken into account while storing the backups. Data loss can cause companies a great loss of revenue. No matter what the reasons behind a data loss are,
whether they are due to human errors or natural causes, crime or disasters, a right
backup strategy is well worth the effort.
Whether a user is sending emails or storing data, chatting with colleagues or browsing
the Internet, encryption is the best tool to ensure the integrity and confidentiality. While
browsing the Internet, users should avoid going to websites that are not encrypted
When it comes to data encryption, there are many encryption tools available for the
protection of the user data, e.g. TrueCrypt that uses complex cryptographic algorithms
to encrypt the data. Even though encryption is known to affect a system performance,
the benefits of encryption are far more than its disadvantages.
8 Conclusion
The aim of the project was to gain a better understanding of different kinds of cyberattacks carried out through the Internet. Cyberspace has evolved very rapidly and
along with it has changed the ways of cyber criminals to choose their victims. While
these attacks most likely will increase by time, the project has suggested some guidelines which can be used in order to be better prepared. People, organizations, schools,
universities and all the other communities where computers are used in the daily life,
should establish strong security policies and help each other to defend against such
Achieving network security is almost an impossible task. Even with the best network
administrators, network security breaches are still likely to occur and will be reported.
The way of thinking of a network administrator has a great effect on the network security.
Security awareness should not be restricted to the IT department, but should be a part
of all areas of the business from the top management to the lowest level of employment in the company. Security policies that are implemented in the company should
have proper guidelines and should be shared in the company and not in the IT department alone.
In an organization, proper training should be held including everyone in the company,
so that the security policies that are defined in the policy formulation will be efficiently
implemented. The training should encompass information not only related to the software but also the hardware usage for the employees.
Since the threats that the business may encounter evolve rapidly, up-to-date
knowledge of countering threats should be disseminated to all the employees of the
company. Devices that the company uses should also be kept up-to-date, for example,
by installing the up-to-date patches and even the operating system.
The history of our society has shown that crime cannot be eliminated forever. However,
with proper measures and precautions it can be decreased to a great extent. Computer
users need to understand their duties and responsibilities. They should be able to defend themselves against all the cyber threats. Self-awareness is very often a key factor
and the only difference between a failed attack attempt and a compromised system.
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