cyber forensics seminar

8/2/2019 Cyber Forensics Seminar

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CYBER FORENSICS


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examine computer evidence properly. Not every department or organization has the

resources to have trained computer forensic specialists on staff.

1. DEFINITION:

Forensic computing is the process of identifying, preserving, analyzing and

presenting digital evidence in a manner that is legally acceptable.(Rodney Mckemmish

1999).

From the above definition we can clearly identify four components:-

IDENTIFYING

This is the process of identifying things such as what evidence is present, where

and how it is stored, and which operating system is being used. From this information

the investigator can identify the appropriate recovery methodologies, and the tools to be

used.


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PRESERVING

This is the process of preserving the integrity of digital evidence, ensuring the

chain of custody is not broken. The data needs to preserved (copied) on stable media

such as CD-ROM, using reproducible methodologies. All steps taken to capture the

data must be documented. Any changes to the evidence should be documented,

including what the change was and the reason for the change. You may need to prove

the integrity of the data in the court of law.

ANALYSING

This is the process of reviewing and examining the data. The advantage ofcopying this data onto CD-ROMs is the fact it can be viewed without the risk of

accidental changes, therefore maintaining the integrity whilst examining the changes.

PRESENTING

This is the process of presenting the evidence in a legally acceptable and

understandable manner. If the matter is presented in court the jury who may have little

or no computer experience, must all be able to understand what is presented and how it

relates to the original, otherwise all efforts could be futile.

Far more information is retained on the computer than most people realize. Its also

more difficult to completely remove information than is generally thought. For these

reasons (and many more), computer forensics can often find evidence or even

completely recover, lost or deleted information, even if the information was intentionally

deleted.

The goal of computer forensics is to retrieve the data and interpret as much information

about it as possible as compared to data recovery where the goal is to retrieve the lost

data.


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2. INTRODUCTION:

In a networked world, there are no safe harbors- if you are on the network, you

are available to everyone else on the network. As economies become more dependent

on information and communication technology (ICT), they are becoming more

vulnerable to network attacks (e.g., Threats to the internet as well as other private and

public networks).

The most serious cyber security risks are those that threaten the functioning of

critical information infrastructures, such as those dedicated to financial services, control

systems for power, gas, drinking water, and other utilities; airport and air traffic control

systems; logistics systems; and government services.

2.1 THREATS TO THE SYSTEM

System threats can be broadly classified into human and environment threats.

Environment threats include power outages, fire and floods. Human threats can be

malicious or non-malicious. A threat is considered malicious if the attack or crime

is committed with full knowledge and intension. A non-malicious threat is one where the

individual does not understand its intent or is ignorant of the action that is about to becommitted.


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For e.g , :-

A disgruntled employee may try to break into the organizations critical business

information to damage the information and the business. This is an example of

malicious human threat.

An ignorant employee may give out information to a hacker without realizing the

consequences. This is an example of non-malicious human threat.

2.2 IMPORTANCE OF SYSTEM FORENSICS

System forensics helps an organization in not only reaching the source of crimeand prosecuting the criminal, but also in organizing their security policy and planning

future security requirements. System forensics helps the organization in the following

way:-

2.2.1 RECOVER DATA THAT YOU THOUGHT WAS LOST FOREVER:-

Computers systems may crash, files may be accidentally deleted, disks may

accidentally be reformatted, viruses may corrupt files, file may be accidentally

overwritten, and disgruntled employees may try to destroy your files. All of this can lead

to loss of your critical data, but computer forensic experts should be able to employ the

latest tools and techniques to recover your data.

2.2.2 ADVICE YOU ON HOW TO KEEP YOUR DATA AND INFORMATION SAFE

FROM THEFT OR ACCIDENTAL LOSS:-

Business today relies on computers. Your sensitive records and trade secrets are

vulnerable to intentional attacks from, for e.g. hackers, disgruntled employees, viruses,

etc. also unintentional loss of data due to accidental deletion, h/w or s/w crashes are


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equally threatening. Computer forensic experts can advice you on how to safeguard

your data by methods such as encryption and back-up.

2.2.3 EXAMINE A COMPUTER TO FIND OUT WHAT ITS USER HAS BEEN DOING:

Whether you are looking for evidence in a criminal prosecution, looking for

evidence in a civil suit, or determining exactly what an employee has been up to. Your

computer forensics expert should be equipped to find and interpret the clues left behind.

2.2.4 SWEEP YOUR OFFICE FOR LISTNENING DEVICES:-

There are various micro-miniature recording and transmitting devices available in

today s hi-tech world. The computer forensic expert should be equipped to conductthorough electronic countermeasure (ECM) sweeps of your premises.

2.2.5 HI-TECH INVESTIGATION:-

The forensic expert should have the knowledge and the experience to conduct

hi-tech investigations involving cellular cloning, cellular subscription fraud, s/w piracy,

data or information theft, trade secrets, computer crimes, misuse of computers by

employees, or any other technology issue.

2.3 COMPUTER FORENSIC METHODOLOGY

Forensic investigation methodology is basically the approach that an investigator

follows to retrieve possible evidence that may exit on a subjects computer system. For

e.g., the following steps should be taken :-


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1. Shut Down the Computer

Depending upon the computer operating system involved, this usually involves

pulling the plug or shutting down a net work computer using relevant operating system

commands. At the option of the computer specialists, pictures of the screen image can

be taken using a camera. However, consideration should be given to possible

destructive processes that may be operating in the background. These can be resident

in memory or available through a modem or network connection. Depending upon the

operating system involved, a time delayed password protected screen saver may

potentially kick in at any moment. This can complicate the shutdown of the computer.

Generally, time is of the essence and the computer system should be shut down or

powered down as quickly as possible

2. Document the Hardware Configuration of The System

It is assumed that the computer system will be moved to a secure location where

a proper chain of custody can be maintained and the processing of evidence can begin.

Before dismantling the computer, it is important that pictures are taken of the computer

from all angles to document the system hardware components and how they are

connected. Labeling each wire is also important so that the original computer

configuration can be restored. Computer evidence should ideally be processed in a

computer hardware environment that is identical to the original hardware configuration.

3. Transport the Computer System to A Secure Location

This may seem basic but all too often seized evidence computers are stored in

less than secure locations. It is imperative that the subject computer is treated as

evidence and it should be stored out of reach of curious computer users. All too often,

individuals operate seized computers without knowing that they are destroying potential

computer evidence and the chain of custody. Furthermore, a seized computer left

unintended can easily be compromised. Evidence can be planted on it and crucial


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evidence can be intentionally destroyed. A lack of a proper chain of custody can 'make

the day' for a savvy defense attorney. Lacking a proper chain of custody, how can you

say that relevant evidence was not planted on the computer after the seizure The

answer is that you cannot. Do not leave the computer unattended unless it is locked in a

secure location! NTI provides a program named Seized to law enforcement computer

specialists free of charge. It is also made available to NTI's business and government in

various suites of software that are available for purchase. The program is simple but

very effective in locking the seized computer and warning the computer operator that

the computer contains evidence and should not be operated

4. Make Bit Stream Backups of Hard Disks and Floppy Disks

The computer should not be operated and computer evidence should not be

processed until bit stream backups have been made of all hard disk drives and floppy

disks. All evidence processing should be done on a restored copy of the bit stream

backup rather than on the original computer. The original evidence should be left

untouched unless compelling circumstances exist. Preservation of computer evidence is

vitally important. It is fragile and can easily be altered or destroyed. Often such

alteration or destruction of data is irreversible. Bit stream backups are much like an

insurance policy and they are essential for any serious computer evidence processing.

5. Mathematically Authenticate Data on All Storage Devices

You want to be able to prove that you did not alter any of the evidence after the

computer came into your possession. Such proof will help you rebut allegations that you

changed or altered the original evidence. Since 1989, law enforcement and military

agencies have used a 32 bit mathematical process to do the authentication process.

Mathematically, a 32 bit data validation is accurate to approximately one in 4.3 billion.

However, given the speed of today's computers and the vast amount of storage

capacity on today's computer hard disk drives, this level of accuracy is no longer

accurate enough. A 32 bit CRC can easily be compromised. Therefore, NTI includes


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two programs in its forensic suites of tools that mathematically authenticate data with a

high level of accuracy. Large hashing number, provides a mathematical level of

accuracy that is beyond question. These programs are used to authenticate data at both

a physical level and a logical level. The programs are called CrcMD5 and DiskSig Pro.

The latter program was specifically designed to validate a restored bit stream backup

and it is made available free of charge to law enforcement computer specialists as part

of NTI's Free Law Enforcement Suite. The programs are also included in our various

suites of forensic software which are sold NTI's clients.

6. Document the System Date and Time

The dates and times associated with computer files can be extremely importantfrom an evidence standpoint. However, the accuracy of the dates and times is just as

important. If the system clock is one hour slow because of daylight-saving time, then file

time stamps will also reflect the wrong time. To adjust for these inaccuracies,

documenting the system date and time settings at the time the computer is taken into

evidence is essential.

7. Make a List of Key Search Words

Because modern hard disk drives are so voluminous, it is all but impossible for a

computer specialist to manually view and evaluate every file on a computer hard disk

drive. Therefore, state-of-the-art automated forensic text search tools are needed to

help find the relevant evidence.

8. Evaluate the Windows Swap File

The Windows swap file is potentially a valuable source of evidence and leads.

The evaluation of the swap file can be automated with several of NTI's forensic tools,

e.g., NTA Stealth, Filter_N, FNames, Filter_G, GExtract and GetHTML. These intelligent

filters automatically identifies patterns of English language text, phone numbers, social


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security numbers, credit card numbers, Internet E-Mail addresses, Internet web

addresses and names of people.

9. Evaluate File Slack

File slack is a data storage area of which most computer users are unaware. It is

a source of significant 'security leakage' and consists of raw memory dumps that occur

during the work session as files are closed. The data dumped from memory ends up

being stored at the end of allocated files, beyond the reach or the view of the computer

user. Specialized forensic tools are required to view and evaluate file slack and it can

prove to provide a wealth of information and investigative leads. Like the Windows swap

file, this source of ambient data can help provide relevant key words and leads that mayhave previously been unknown.

10. Evaluate Unallocated Space (Erased Files)

The DOS and Windows 'delete' function does not completely erase file names or

file content. Many computer users are unaware the storage space associated with such

files merely becomes unallocated and available to be overwritten with new files.

Unallocated space is a source of significant 'security leakage' and it potentially contains

erased files and file slack associated with the erased files. Often the DOS Undelete

program can be used to restore the previously erased files. Like the Windows swap file

and file slack, this source of ambient data can help provide relevant key words and

leads that may have previously been unknown to the computer investigator.

11. Search Files, File Slack and Unallocated Space for Key Words

The list of relevant key words identified in the previous steps should be used to

search all relevant computer hard disk drives and floppy diskettes. There are several

forensic text search utilities available in the marketplace. NTI's forensic search

TextSearch NT can be used for that purpose and it has been tested and certified for


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accuracy by the U. S. Department of Defense. This powerful search tool is also included

as part of NTI's suites of software tools.

12. Document File Names, Dates and Times

From an evidence standpoint, file names, creation dates, last modified dates and

times can be relevant. Therefore, it is important to catalog all allocated and 'erased'

files. NTI includes a program called FileList Pro in its various suites of forensic tools.

The FileList Pro program generates its output in the form of a database file. The file can

be sorted based on the file name, file size, file content, creation date, last modified date

and time. Such sorted information can provide a timeline of computer usage.

13. Identify File, Program and Storage Anomalies

Encrypted, compressed and graphic files store data in binary format. As a result,

text data stored in these file formats cannot be identified by a text search program.

Manual evaluation of these files is required and in the case of encrypted files, much

work may be involved. NTI's TextSearch Plus program has built in features that

automatically identify the most common compressed and graphic file formats. The use

of this feature will help identify files that require detailed manual evaluation. Depending

on the type of file involved, the contents should be viewed and evaluated for its potential

as evidence.

14. Evaluate Program Functionality

Depending on the application software involved, running programs to learn their

purpose may be necessary. NTI's training courses make this point by exposing the

students to computer applications that do more than the anticipated task. When

destructive processes are discovered that are tied to relevant evidence, this can be

used to prove willfulness. Such destructive processes can be tied to 'hot keys' or the

execution of common operating commands tied to the operating system or applications.

Before and after comparisons can be made using the FileList Pro program and/or


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mathematical authentication programs. All these tools are included in most of NTI's

suites of forensic tools

15. Document Your Findings

As indicated in the preceding steps, it is important to document your findings as

issues are identified and as evidence is found. Documenting all of the software used in

your forensic evaluation of the evidence including the version numbers of the programs

used is also important. Be sure that you are legally licensed to use the forensic

software.

2.4 APPLICATION OF COMPUTER FORENSICS

System forensics is not different from any other forensic science when it comes

to application. It can be applied to any activity, where other mainstream traditional

forensics such as DNA mapping is used, if there has been an involvement of a system

or computer in the event.

Some of the common applications of computer forensics are:-

2.4.1 FINANCIAL FRAUD DETECTION:-

Corporates and banks can detect financial frauds with the help of evidence

collected from systems. Also , insurance companies can detect possible fraud in

accident, arson, and workman s compensation cases with the help of computer

evidence.


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2.4.2 CRIMINAL PROSECUTION:-

Prosecutors can use computer evidence to establish crimes such as homicides,

drug and false record-keeping, financial frauds, and child pornography in the court of

law.

2.4.3 CIVIL LITIGATION:-

Personal and business records found on the computer systems related to fraud,

discrimination, and harassment cases can be used in civil litigations.

2.4.4 CORPORATE SECURITY POLICY AND ACCEPTABLS USE VIOLATIONS:-

A lot of computer forensic work done is to support management and human

resources (HR) investigations of employee abuse. Besides cyber crimes and system

crimes, criminals use computers for other criminal activities. In such cases , besides the

traditional forensics, system forensic investigation also plays a vital role.

3. CYBER CRIME:

Cyber crime is addressed in the broadest sense, in a way that most emerging

crimes today involve the use information technology. The terms Computer Crime ,

Computer Related Crimes , Internet Crime , Online Crimes , Hi -Tech Crimes ,

Information Technology Crime , and Cyber Crimes are being used interchangeably.

Cyber crime is hard to detect, thus giving the perpetrators plenty of time to flee

the area in which the crime was committed, because of this fact the criminals can be in

another country far away from the scene of the crime by the time it is detected.

Cyber Crimes differ from most terrestrial crimes in four ways:

They are easy to learn how to commit


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they require few resources relative to the potential damage caused

they can be committed in a jurisdiction without being physically present in

it and

they are often not clearly illegal.

The development of information technology and the widening usage of the

Internet have made it possible for cyber crimes to happen. Some people argue that

cyber crime gives advantages to certain individuals because it gives them an

opportunity to enhance their computer skills and make a profit out of it. However, that is

far from truth. In reality, cyber crime kills e-commerce industry as seen through the

unleashing of viruses, fraud, and variety of tools available on the net and unauthorizeduse of computers.

The first recorded cyber crime took place in the year 1820. That is not surprising

considering the fact that the abacus, which is thought to be the first earliest form of computer,

has been around since 3500 B.C. in India, Japan and China. The era of modern computers,

however, began with the analytical engine of Charles Babbage.

Maintaining the security of a computer system and electronic transactions

involves checking:

Adequate physical security to prevent accidental or intentional damage to the

computer system and related equipment.

Software and data file security to ensure computer programs and data files are

not altered accidentally or deliberately.

Techniques for maintaining transaction data controls and for analyzing the

reasonableness of transactions to detect and report possible crime attempts.

Use of computer identification methods to restrict unauthorized individuals from

initiating transactions to customer accounts.


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Secure communications networks to prevent unauthorized interception or

alteration of electronic data.

Adequate internal controls to prevent, detect, and correct computer crime and

other concerns.

3.1 EXAMPLES OF CYBER CRIME:3.1.1 Email Spoofing:

Email spoofing is email activity in which the sender address and other parts of

the email header are altered to appear as though the email originated from a different

source. Because core SMTP doesn't provide any authentication, it is easy to

impersonate and forge emails.

Although there are legitimate uses, these techniques are also commonly used

in spam and phishing emails to hide the origin of the email message.

By changing certain properties of the email, such as the From , Return-

Path and Reply-To fields (which can be found in the message header), ill-intentioned
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users can make the email appear to be from someone other than the actual sender. The

result is that, although the email appears to come from the address indicated in

the From field (found in the email headers), it actually comes from another source.

Prior to the advent of unsolicited commercial email (spam) as a viable business

model, "legitimately spoofed" email was common. For example, a visiting user might

use the local organization's SMTP server to send email from the user's foreign address.

Since most servers were configured as open relays, this was a common practice. As

spam email became an annoying problem, most of these "legitimate" uses fell victim to

anti-spam techniques.

It is much more difficult to spoof or hide the IP or Internet Protocol address. TheIP address is a 32 or 128 bit numerical label assigned to each device participating in a

network and originates through the network provider making it more difficult to spoof or

hide. Although this kind of verification is difficult for individual users, companies can use

this technology as well as others such as cryptographic signatures (e.g., PGP "Pretty

Good Privacy" or other encryption technologies) to exchange authenticated email

messages. Authenticated email provides a mechanism for ensuring that messages are

from whom they appear to be, as well as ensuring that the message has not been

altered in transit. Similarly, sites may wish to consider enabling SSL/TLS in their mail

transfer software. Using certificates in this manner increases the amount of

authentication performed when sending mail.

Example: Sameer spoofs her email and sends obscene messages to all her

acquaintances. Since the emails appear to have originated from Pooja, her friends

could take offence and relationships could be spoiled for life.

Email spoofing can also cause monetary damage. Misinformation about

companies are sent through emails and thus large lose will occur to companies in form

of money and customers.
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3.1.2 FORGERY:

Forgery is the process of making, adapting, or imitating objects, statistics,

or documents with the intent to deceive. Copies, studio replicas, and reproductions are

not considered forgeries, though they may later become forgeries through knowing andwillfulmisrepresentations. Forging money or currency is more often

called counterfeiting. But consumer goods may also be counterfeits if they are not

manufactured or produced by the designated manufacture or producer given on

the label or flagged by the trademark symbol. When the object forged is a record

or document it is often called a false document.

Counterfeit currency notes, postage and revenue stamps, mark sheets, etc can

be forged using sophisticated computers, printers and scanners.

3.1.3 UNAUTHORIZED ACCESS TO COMPUTER SYSTEMS OR

NETWORKS:

This occurs when a user/hacker deliberately gets access into someone else s

network either to monitor or data destruction purposes .

HOW TO PREVENT UNAUTHORIZED COMPUTER ACCESS:

FIREWALL:

A system designed to prevent unauthorized access to or from a private network.

Firewalls can be implemented in both hardware and software, or a combination of both.

Firewalls are frequently used to prevent unauthorized Internet users from accessing

private networks connected to the Internet, especially intranets . All messages entering

or leaving the intranet pass through the firewall, which examines each message and

blocks those that do not meet the specified security criteria. There are several firewall

techniques, including:
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Packet Filter: Looks at each packet entering or leaving the network and accepts

or rejects it based on userdefined rules. Packet filtering is fairly effective and

transparent to users, but it is difficult to configure. In addition, it is susceptible to IP

spoofing.

Application gateway: Applies security mechanisms to specific applications,

such as FTP and Telnet servers. This is very effective, but can impose performance

degradation.

Circuitlevel gateway: Applies security mechanisms when a TCP or UDP

connection is established. Once the connection has been made, packets can flow

between the hosts without further checking.

Proxy server: Intercepts all messages entering and leaving the network. The

proxy server effectively hides the true network addresses.

In practice, many firewalls use two or more of these techniques in concert. A firewall is

considered a first line of defense in protecting private information. For greater security,

data can be encrypted.

3.1.4 EMAIL BOMBING:

In Internet usage, an email bomb is a form of net abuse consisting of sending

huge volumes of email to an address in an attempt to overflow the

mailbox or overwhelm the server where the email address is hosted in a denial-of

service attack.

3.1.4.1 Methods Of email bombing:

There are two methods of perpetrating an email bomb: mass mailing and list

linking.
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Mass mailing:

Mass mailing consists of sending numerous duplicate mails to the same email

address. These types of mail bombs are simple to design but their extreme simplicity

means they can be easily detected by spam filters. Email-bombing using mass mailing

is also commonly performed as a DDoS attack by employing the use of

"zombie" botnets; hierarchical networks of computers compromised by malware and

under the attacker's control. Similar to their use in spamming, the attacker instructs the

botnet to send out millions or even billions of emails, but unlike normal botnet

spamming, the emails are all addressed to only one or a few addresses the attacker

wishes to flood. This form of email bombing is similar in purpose to other DDoS flooding

attacks. As the targets are frequently the dedicated hosts handling website and email

accounts of a business, this type of attack can be just as devastating to both services of

the host.

This type of attack is more difficult to defend against than a simple mass-mailing

bomb because of the multiple source addresses and the possibility of each zombie

computer sending a different message or employing stealth techniques to defeat spam

filters.

List linking:

List linking means signing a particular email address up to several email list

subscriptions. The victim then has to unsubscribe from these unwanted services

manually. In order to prevent this type of bombing, most email subscription services

send a confirmation email to a person's inbox when that email is used to register for a

subscription. This method of prevention is easily circumvented: if the perpetrator

registers a new email account and sets it to automatically forward all mail to the victim,he or she can reply to the confirmation emails, and the list linking can proceed.
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Zip bombing:

A ZIP bomb is a variant of mail-bombing. After most commercial mail servers

began checking mail with anti-virus software and filtering certain malicious file

types, EXE, RAR, Zip, 7-Zip. Mail server software was then configured to unpack

archives and check their contents as well. A new idea to combat this solution was

composing a "bomb" consisting of an enormous text file, containing, for example, only

the letter z repeating millions of times. Such a file compresses into a relatively small

archive, but its unpacking (especially by early versions of mail servers) would use a

greater amount of processing, which could result in a DoS (Denial of Service).

3.1.5 Data Diddling:

This kind of attack involves altering raw data just before it is processed by a

computer and the changing it back after the processing is completed.

Examples include forging or counterfeiting documents used for data entry and

exchanging valid disks and tapes with modified replacements.

To deal with this type of crime, a company must implement policies and internal

controls. This may include performing regular audits, using software with built-in

features to combat such problems, and supervising employees.

3.1.6 Computer Viruses:

Computer viruses are programs that can attach themselves to other programs or

files. The virus infected files can then become carriers of the virus, or become damaged

in some way. The virus may effect computer services, displaying messages or playing

sounds, or may crash the operating system so that the computer won t run as expected

(if at all).

You can prevent computer viruses by installing an anti-virus program on your

computer, which scans files for known viruses. There are a number of these programs

on the market, and they can be purchased from software stores or acquired on the
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Internet. Once installed, you will need to regularly update anti-virus files, which are used

to detect and remove viruses from your system.

3.1.7 Hackers and Crackers:

In computer jargon, "hacker" has a variety of meanings, including being

synonymous with programmers and advanced computer users. In these cases, it refers

to someone who hacks away at a keyboard for long periods of time, performing any

number of computer-related tasks. In recent years, hacking has come to mean the

same as another term "cracker," which is a person who cracks the security of a system

or computer application. Hacking (and cracking) now refers to the act of gaining

unauthorized access to a computer, network, Web site, or areas of a system.

A person may hack their way into a system for a variety of reasons; curiosity, the

challenge of breaking through security measures, or to perform malicious actions and

destroy or steal data. All to often, it involves performing mischief and damaging a Web

site or corporate network in some manner.

Commonly, hackers will impersonate a valid user to gain access to a system. If

the system requires a username and password before allowing entry, a hacker may

take an authentic user s identity. On a network or an office with Internet access, a

hacker can impersonate someone else by simply sitting at the unattended workstation


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of another user who hasn t logged off. It also commonly occurs when someone has an

easy to guess username and password, or allows this information to be known by

others.

Another common method hackers use to gain access is to guess or crack ausername and password that s used to access a computer, network, or Internet

account. To prevent being hacked in this manner, you should use passwords that are

difficult to guess. You should also make your passwords a mixture of letters, numbers,

and special characters (e.g. !, @, #, $, %, , &, *). You should change your password at

regular intervals, and set a minimal length to passwords (such as being a minimum of

six or eight characters).

3.1.8 Salomi Attacks:

These attacks are used for the commission of financial crimes. The key here is to

make the alteration so significant that in a single case it would go completely unnoticed.

E.g., a bank employee inserts a program, into the bank server s, which deducts a small

amount of money 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.

3.2 Computer Fraud

Any incident involving computer technology in which there is a victim who

suffered (or could have suffered) a loss and a perpetrator who by intention made (or

could have made) a gain is the defined as computer fraud.

3.3 INVESTIGATION


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Investigation is the process of collecting, analyzing, and recovering, evidence,

and presenting, a report detailing a crime. Evidence is the key factor that determines a

crime and helps prosecute the guilty in the court of law.

The investigation process consists of procedures and techniques for finding out

what happened, what damage was done, and to what extent, whether the intruder is still

a threat, and whether any fixes still need to be implemented. An investigation, to a great

extent depends on the skill of the investigator or forensic expert.

3.4 IMPORTANCE OF INVESTIGATION

With the increase in system and cyber crime and the uses of new tools and

techniques, organizations have realized that it is not only important to prevent thesecrimes and protect information, but to trace the source of crime.

Tracing the footprint of a computer crime is important because:

3.4.1 It helps to understand the system security weaknesses:-

Investigating a computer crime helps an organization understand if the system

were exploited for a weakness in the security system. For e.g. administrators need not

know if an existing flaw helped someone transfer money from one bank account to

another, and whether that flaw still exists.

3.4.2 It helps to understand security violation techniques:-

The techniques could range from implanting spyware in the systems, to recruiting

internal employees to gain security information to sabotage organizations from within.

An investigation might collect information such as each employee s involvement, and

the way the crime was organized.


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3.4.3 It helps to identify future security needs:-

These investigations also provide information on new tools that were used or are

being developed. The investigations may help companies and even law-enforcement

agencies discover future trends and design new tools to protect network s and

information.

3.4.4 It helps to prosecute criminals:-

If the crime has led to financial and other losses, prosecution may be initiated

against the criminals. Investigation becomes extremely important, because without it,

there can be no case.

3.5 COMPONENTS OF INVESTIGATION

An investigation has three important components. They are:-

3.5.1 EVIDENCE:-

Almost all types of investigation of a system crime relies on the evidence

obtained from the target computer. You can collect evidence for a computer crime by

analyzing digital data such as e-mails, files, and other system information. Evidence

provides vital information about the crime in terms of tools and techniques that were

used.

E.g. Information in a system s RAM can provide clues about the last program executed

that may have been used in computer crime. Such type of evidence is volatile as

compared to evidence on paper and must be preserved. Digital evidence may include

deleted files or e-mails, computer logs, spreadsheets, and accounting information.

electronic data include record, file, source code, program, computer manufacturer

specifications, and other information on the computer storage devices.

Digital information can take the following forms:-


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- word processing documents

- personal records

- customer lists

- financial information

- e-mail via the local network or internet

- system and application logs

- voice mail transcript

- electronic scheduling system

3.5.2 Linking the chain of evidence:-

After evidence of a crime has been found it is important to figure out thecomplete sequence of activities that may have taken place during the commission of

crime.

3.5.3 Documentation:-

It is the most important factor in investigation of system crimes. Each piece of

evidence must be recorded systematically for the law, as well as for better analysis of

the system. Failure to do so weakens the investigation, and the result may not be

correct.

3.6 STEPS FOR INVESTIGATION

Every investigation follows a well-defined procedure. The procedure involves the

following four steps:-

3.6.1 COLLECTING EVIDENCE:

The first and the most important step in an investigation is collection of evidence.

sAs an investigator, it is important to understand, to know, and to choose what is to be


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treated as evidence from the available information. The evidence varies from situation

to situation. E.g., the evidence from investigating a hard disk may be different from

investigating a CD-ROM drive. It is important that the investigator is up-to date with the

new technologies, and of what they can and cannot do.

You can locate digital evidence at various sources such as:-

- Workstations

- Servers

- Network attached storage

- Scanners

- Proxy server and ISP logs

3.6.2 ANALYZING EVIDENCE:

The second step is analyzing the evidence. it requires careful and systematic

study to determine the answer to questions such as:-

- What damage was done

- Why was the damage done

- What information is there about the technique used to inflict damage

- Why this set of information serve as good evidence

Answering these questions gives you a clear picture of the extent and nature of

damage.

There are different tools and techniques that are used to commit computer crime.

It is important to identify the tools as well as the techniques. These provide the all

important footprints of the crimes. These footprints can be evaluated later to translate

them into meaningful sources of evidence. Many vulnerability software manufacturers

recognize the fact that their software is also effective hacking tools, so they are


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designed to leave their identity traces along the path they followed, this serves as strong

forensic evidence against the acts of computer crimes and criminals.

3.6.3 RECOVERING EVIDENCE:

There is certain evidence that is removed by computer criminals for various

reasons. At times, there are changes in the evidence simply because the system was

rebooted. As an investigator, you must attempt to recover all the data that might have

been tampered with, and locate the information that may be of some evidence. e.g. if

some data has been deleted from the hard disk, it might be recovered to obtain more

accurate information about what actually had happened.

3.6.4 PRESERVING EVIDENCE:

After all the evidence as been collected, it is important to preserve it, as it existed

during or soon after the crime. The procedure should follow a well-devised technique to

avoid any changes in the data. Following is a checklist used to ensure that the evidence

remains protected and preserved:-

- The evidence is not damaged or altered due to tools and techniques used for

investigation.

- The evidence is protected from mechanical or electromagnetic damage.

- The target computer is not infected by any virus during the investigation process.

- Business operations of the organization are not affected during the investigation.

- Continuing chain of evidence is maintained.

3.7 Computer Crime Investigator:

The computer crime investigator is a specialist in criminal investigation, data

processing, auditing, and accounting. His knowledge of data processing should include

computer operations, systems design and analysis, programming, and project

management.


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A primary element in a computer crime investigation course is the manner in

which it is structured and whether it contains all the vital areas of required knowledge. A

computer crime investigation curriculum should include the following:

1. The types of threats and vulnerabilities to which a computer is susceptible.

2. Data processing concepts relative to software (programming) and hardware (the

equipment itself).

3. Types of computer crimes.

4. Investigative methodology including investigative procedures, forensic

techniques, review of technical data systems, investigation planning,

interview/interrogation techniques, information gathering and analysis, and case

presentation techniques.

3.8 TYPES OF INVESTIGATION

Investigations are done on different lines under different situations. Although

investigation techniques vary, they can be categorized broadly into two types:-- Physical investigation- Logical investigation

These investigations give information about the system usage patterns, including

application and resource usage. This information might require application monitoring

tools such as sniffers.

3.8.1 PHYSICAL INVESTIGATION

It includes identifying or locating physical evidence, such as removal of computer

hardware. Certain behavior or incident could trigger a physical investigation. Some

examples are:-

- Unusual or unauthorized late hours

- Changes in the pattern of system usage

- Changes in the login system


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- Making physical attempts to reach connected physical devices.

The above are some of the physical forms of malicious intent that needs to be

monitored through physical investigation, such as checking the system for changes in

hardware, network monitoring s/w, or asset management s/w to keep a close eye on the

systems physical assets.

3.8.2 LOGICAL INVESTIGATION

It can be referred as digital investigation. Logical investigation takes a look at log

files that can be used as evidence against the criminal. It requires a well designed

security policy that clearly defines the process for logging information. It is importantthat the logs be maintained systematically. Some of the logical investigation

requirements are:-

- No modifications :-

The system logs should not be modified at all. The system should remain in the

same state as it was when the crime occurred or else it could lead to loss of evidence.

- Log date and time stamp:-It is important that the date and time stamp of the log has not been changed.

Otherwise this will introduce a difference when connecting evidence to the change of

activity that may have occurred at time of the crime.

- Logs of the system:-

The logs of the system being investigated must be checked and studied to

analyze their integrity.

- System registry:-

System registry keys must be checked to identify the authenticity of the last

logged-in users and the integrity of critical files.

- forensic imaging tool:-

forensic imaging tool must be used to make multiple copy of the hard disk that

have been taken for investigation. Bib-by-bit copy of the hard disk must be made so that


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no portion of the hard disk whether filled or empty, is left without being copied. An

example of forensic imaging tool is SETBACK.

Table 2.1 shows sample of log user

RECORD 1 RECORD 2

User Id: user1 User Id: user 2

TimeL showed: 12:30:00 TimeL showed: 12:40:50

DateL showed: 22-07-2003 DateL showed: 22-07-2003

TimeS showed: 10:40:00 TimeS showed: 10:50:50

DateS showed: 22-07-2003 DateS showed: 22-07-2003

Duration: 20mins Duration: 30minsSystem Id: s1 System Id: s1

Table 2.1

CHAPTER 4

COMPUTER FORENSIC TECHNOLOGY

Computer forensics tools and techniques have proven to be a valuable resource

for law enforcement in the identification of leads and in the processing of computer-related evidence. Computer forensic tools and techniques have become important

resources for use in internal Investigations, civil law suits, and computer security risk

management.

Forensic S/w tools and methods can be used to identify passwords, logons, and

other information that is automatically dumped from the computer memory. Such

forensic tools can be used to tie a diskette to the computer that created it. Some of the

tools used are as follows:

4.1 TYPES OF LAW ENFORCEMENT COMPUTER FORENSIC TECHNOLOGY

4.1.1 MIRROR IMAGE BACKUP SOFTWARE

SafeBack is a sophisticated evidence-preservation tool. It was developed

primarily for processing of computer evidence. This tool has become the industry


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standard in the processing of computer evidence in the world. SafeBack is used to

duplicate all storage areas on a computer hard disk drive. The drive size creates no

limitation for this tool. It is used to create mirror-image backups of partitions of hard-

disk, which may contain multiple partitions and/or operating systems. The back-up

image files, created by SafeBack, can be written to essentially any writable magnetic

storage device, including SCSI tape backup units.

PROGRAM FEATURES AND BENEFITS

- Dos based for ease of operating and speed

- Provides a detail audit trail of the backup process for evidence documentation

purpose.- Checks for and duplicates data stored in sectors wherein the sector CRC does not

match the stored data.

- Copies all areas of the hard disk drive.

- Allows the archive of non-Dos and non-Windows HDD, (Unix on an Intel based

computer).

- Allows for the back-up process to be made via the printer port.

- Duplicate copies of HDD can be made from HD to HD in direct mode.

- SafeBack image file can be stored as one large file or separate files of fixed sizes.

This feature is helpful in making copies for archives on CDs

- Tried and proven evidence-preservation technology with a 10-year legacy of success

in government agencies.

- Creates a non-compressed file that is an exact and unaltered duplicate of the original.

This feature eliminates legal action against the potential alteration of evidence through

compression or translation.

- Fast and efficient. Depending on the hardware configuration involved, the data transfer

rate exceeds 50 million bytes per minute during the back-up process.

- Copies and restores one or more partitions containing one or more operating systems.

- Can be used accurately to copy and restore Windows NT and Windows 2000 drives in

raid configuration.
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- Writes to SCSI tape backup units or HDD.

4.1.2 ANADISK DISKETTE ANALYSIS TOOL

AnaDisk turns your PC into a sophisticated diskette analysis tool. The software

was originally created to meet the needs of the U.S. Treasury department.

PRIMARY USES

- Security reviews of floppy diskettes for storage

- Duplication of diskettes that are non-standard or that involve storage anomalies.

- Editing disks at a physical sector level.- Searching for data on FDs in traditional and non-traditional storage areas.

- Formatting disks in non-traditional ways for training purpose and to illustrate data-

hiding techniques.


- Dos based for ease of operation and speed

- Keyword searches can be conducted at a very low level and on disks that have been

formatted with extra tracks. This feature is helpful in the evaluation of disks that may

involve sophisticated data-hiding techniques.

- All dos formats are supported and many non-dos formats, (apple machintosh, unix tar,

and many others. If the disk fits in the drive, it is likely that AnaDisk can be used to

analyze it.

- Allows custom formatting of disks with extra tracks and sectors.

- Scans for anomalies will identify odd formats, extra tracks and extra sectors. Data

mismatches concerning certain file formats are also identified when file extensions have

been changed in an attempt to hide data.

- This S/w can be used to copy any disk, including most copy-protected disks.


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4.1.3 TEXT SEARCH PLUS

TextSearch plus was specifically designed and enhanced for speed and

accuracy in security reviews. It was widely used by classified government agencies and

corporations that support these agencies. The s/w is also used by hundreds of law

enforcement agencies throughout the world in computer crime investigations.

PRIMARY USES

- Used to find occurrences of words or strings of text in data stored in files, slack, and

unallocated file space.

- Used in exit reviews of computer storage media from classified facilities.- Used in internal audits to identify violations of corporate policy.

- Used by fortune 500 corporations, government contractors, and government agencies

in security reviews and risk assessments.

- Used in corporate due diligence efforts regarding proposed mergers.

- Used to find occurrences of keywords strings of text in data found at a physical sector

level.

- Used to find evidence in corporate, civil, and criminal investigation that involve

computer-related evidence.

- Used to find embedded text in formatted word processing documents.


- Dos based for ease of operation and speed

- Small memory footprint, which allows the s/w to run on even the original IBM PC.

- Compact program size, which easily fits on one FDisk with other forensic s/w utilities.

- Searches files, slack, and erased space in one fast operation.

- Has logical and physical search options that maintain compatibility with government

security review requirements.

- User defined search configuration feature.
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- User configuration is automatically saved for future use.

- Embedded words and strings of text are found in word processing files.

- Alert for graphic files (secrets can be hidden in them)

- Alert for compressed files

- High speed operation. This is the fastest tool on the market, which makes for quick

searches on huge HDDs.

- False hits d on t stop processing.

- Screen and file output.

- Government tested specifically designed for security reviews in classified

environments.

4.1.4 INTELLIGENT FORENSIC FILTER

This enhanced forensic filter is used to quickly make sense of nonsense in

analysis of ambient computer data. This tool is so unique that process patents have

been applied for with the U.S. patent office.

Filter_I relies on preprogrammed artificial intelligence to identify fragments of

word processing communications, network passwords, fragments of e-mail

communication, fragments of internet chat room communication, fragments of internet

news group posts, encryption passwords, network log-ons, database entries, credit card

numbers, social security numbers, and the first and last name of individuals who have

been listed in communication involving the subject computer. This s/w saves days in

processing of computer evidence when compared to traditional methods.

PRIMARY USES

- Used covertly to determine prior activity on a specific computer.

- Used to filter ambient computer data, the existence of which the user is normally

unaware of (memory dumps in slack file, window swap files, windows DAT files and

erased file space).

- The ideal tool for use by corporate and government internal auditors.


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- The ideal tool for use by corporate and government computer security specialists.

- The ideal tool to use for corporate, military, and law enforcement investigators.

- Perfect for covert intelligence gathering when laws permit and you have physical

access to the subject computer.


- DOS based for speed. The speed of operation is amazing.

- Automatically processes any binary data object.

- Provides output in an ASCII text format that is ready for import into any word

processing application.

- Capable of processing ambient data files that are up to 2GB in size.

4.2 TYPES OF BUSINESS COMPUTER FORENSIC TECHNOLOGY

Lets look at the following types of business computer forensics technology:

4.2.1 REMOTE MONITORING OF TARGET COMPUTERS

Data interception by remote transmission (DIRT) from codex data system (CDS),

Inc, is a powerful remote control monitoring tool that allows stealth monitoring of all

activity on one or more target computers simultaneously from a remote command

center. No physical access is necessary. Application also allows agents to remotely

seize and secure digital evidence prior to physically entering suspect premises.

4.2.2 CREATES TRACKABLE ELECTRONIC DOCUMENT

Binary audit identification transfer (BAIT) is another powerful intrusion detection

tool from CDS that allows the user to create trackable electronic documents.

Unauthorized intruders who access, download, and view these tagged documents will


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be identified (including their location) to security personnel. BAIT also allows security

personnel to trace the chain of custody and chain of commands of all who possess the

stolen electronic document.

4.2.3 THEFT RECOVERY SOFTWARE FOR YOUR PCs AND LAPTOPS

If your pc or laptop is stolen, is it smart enough to tell you where it is CDs has a

solution: PC PhoneHome-another software application that will track and locate a lost or

stolen pc or laptop anywhere in the world. It is easy to install. It is also completely

transparent to the user. If your PhoneHome computer is lost or stolen, all you need to

do is make a report to the local police and call CDS 24 hour command center. CDSs

recovery specialists will assist local law enforcement in recovery of your property.

4.2.4 BASIC FORENSIC TOOLS AND TECHNIQUES

The digital detective workshop from CDS was created to familiarize investigators

and security personnel with the basic techniques and tools necessary for a successful

investigation of internet and computer related crimes. Topics include:

- Types of computer crimes

- Cyber law basics

- Tracing e-mail to source.

- Digital evidence acquisition

- Cracking password

- Monitoring computer remotely

- Tracking online activity

- Finding and recovering hidden and deleted data

- Locating stolen computers

- Creating trackable files

- Identifying software pirates and so on.


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- Strong analytical skills Patience to invest days in taking computers apart in search of

evidence

- Strong computer science fundamentals

- Broad understanding of security vulnerabilities

- Strong system administrative skills

- Excellent verbal and written communication skills

- Knowledge of the latest intruder tools

- Knowledge of and experience with the latest forensic tools

- Knowledge of cryptography and steganography

- Strong understanding of the rules of evidence and evidence handling

-The ability to be an expert witness in a court of law

5.2 TRAINING

There are many training courses to learn the art of computer forensics.

eSec Limited and Found stone Education - conduct 4 day training courses on Incident

Response and Computer Forensics.

Guidance Software - offers six, four day courses: EnCase Introduction to Computer

Forensics, EnCase Intermediate Analysis and Reporting, EnCase Internet and E-Mail

Examinations, EnCase EScript Programming, EnCase Prosecutor Training, and

EnCase Advanced Training. Each has a curriculum designed to address the various

skill levels of the students. Not all of these courses are available in Australia. Guidance

Software offers the EnCase Certified Examiner (EnCE) program. Certification is

available to anyone who meets the minimum requirements for the program. Information

can be found at http://www.guidancesoftware.com/html/ence.htm.
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6. Top Cyber Forensics Tools:

forensic is an interesting domain which is coupled with technical advances and

the ability to use them effectively. Cyber forensic primarily is used in the investigation of

cyber crimes (i.e., crimes that occur over and on the technology front). However this

need not be the case, since most forensic techniques and tools are also used for

scientific purposes and research. With serious issues like terrorism that threaten the

national integrity of a country it is only wise to learn and know the tools of the trade that

terrorists use against the state. Cyber forensic tools aid not only in investigating crime

cases but also for drafting and creating hard evidences for the same. Let us evaluate

just some of these tools that have been used since long by forensic investigators,

scientists and some notorious elements alike:

6.1 X-Ways WinHex:

WinHex is used as a universal hexadecimal editor and is primarily useful in low-

level data processing, file inspection, digital camera card recovery, recovery of files

even from corrupt files systems, etc. This is one heck of a powerful tool and can

especially be used in gathering digital evidence.

6.2 FirstOnScene (FOS):FOS is the only one tool of its kind. It is rather a visual basic script code than a

executable binary file. First On Scene works with other tools such as PSTools,

LogonSessions, FPort, NTLast, PromiscDetect, FileHasher, etc. to gather an evidence

log report. This log report can further be analyzed by forensic experts to extract

important information.

6.3 Rifiuti:

Rifiuti is a unique tool that aids investigators in finding the very last details of your

system's recycle bin folders. Rifiuti is useful to gather critical information on all your

delete and undelete activities.

6.4 Pasco:


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Pasco is a Latin word for "browse". Pasco helps in the analysis of the contents of

internet explorer's cache. So in short it can be particularly useful to gather internet

activity records from a target computer.

6.5 Galleta:

Galleta is a Spanish word that means "cookie". Galleta is useful in examining the

contents of cookie files on your machine. Cookie files are basically temporary internet

files used by websites to maintain their indigenous logs for tracking and other such

purposes.

6.6 Forensic Acquisition Utilities (FAU):

Forensic Acquisition Utilities is a set of forensic tools such as md5 checker, filewiper, etc. used for assorted purposes in research and investigation.

6.7 NMap:

NMap is particularly associated with network security. NMap is a port scanner

tool that helps find open ports on a remote machine. What separates NMap from other

tools is its ability to evade source machine identity and to work without causing any

Intrusion Detection System (IDS) alarms to go of.

6.8 Ethereal:

Ethereal is another network security tool which is not a port scanner but rather a

network packet sniffer. Ethereal sniffs data packets over the network and can provide

investigators with incoming/outgoing data that is sent over a network. However, ethereal

itself cannot be useful in cases where strong encryption algorithms are in place at the

source and destination computers.

6.9 BinText:

BinText does not directly investigate but can be useful to browse through

gathered evidence files such as that of log files generated by other forensic tools.

BinText can be used for pattern matching and filtering these log files.


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6.10 PyFlag Tools:

PyFlag are a couple of tools used for log analysis and can be a very effective tool

for investigators if coupled and used with other forensic tools.

7. Anti forensics Techniques:

Anti-forensic techniques try to frustrate forensic investigators and

their techniques. This can include refusing to run when debugging mode is enabled,

refusing to run when running inside of a virtual machine, or deliberately overwriting data.

Although some anti-forensic tools have legitimate purposes, such as overwriting

sensitive data that shouldn't fall into the wrong hands, like any tool they can be abused.

Secure Data Deletion

Securely deleting data, so that it cannot be restored with forensic methods.

Overwriting programs typically operate in one of three modes:

1. The program can overwrite the entire media.

2. The program can attempt to overwrite individual files. This task is complicated by

journaling file systems: the file itself may be overwritten, but portions may be left

in the journal.

3. The program can attempt to overwrite files that were previously deleted but left

on the drive. Programs typically do this by creating one or more files on themedia and then writing to these files until no free space remains, taking special

measures to erase small files for example, files that exist entirely within the

Windows Master File Table of an NTFS partition (Garfinkel and Malan, 2005).
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Preventing Data Creation

Prevent the creation of certain data in the first place. Data which was never

there, obviously cannot be restored with forensic methods.

For example, a partition can be mounted read-only or accessed through the raw

device to prevent the file access times from being updated. The Windows registry key

HKLM\SYSTEM\CurrentControlSet\Control\FileSystem\NtfsDisableLastAccessUpdate

can be set to 1 to disable updating of the last -accessed timestamp; this setting is

default under Windows Vista (Microsoft 2006).

Cryptography, Steganography, and other Data Hiding Approaches

Encrypted Data

Cryptographic file systems transparently encrypt data when it is written to the

disk and decrypt data when it is read back, making the data opaque to any attacker (or

CFT) that does not have the key. These file systems are now readily available for

Windows, Mac OS, and Linux. The key can be protected with a passphrase or stored on

an auxiliary device such as a USB token. If there is no copy of the key, intentionally

destroying the key makes the data stored on the media inaccessible (Boneh and Lipton,

1996). Even if the cryptographic system lacks an intentional sanitization command or

self -destruct, cryptography can still be a potent barrier to forensic analysis if the

cryptographic key is unknown to the examiner.

Cryptography can also be used at the application level. For example, Microsoft

Word can be configured to encrypt the contents of a document by specifying that the

document has a password to open. Although older versions of Microsoft Word

encrypted documents with a 40-bit key that can be cracked with commercial tools,

modern versions can optionally use a 128-bit encryption that is uncrackable if a secure

passphrase is used.


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Encrypted Network Protocols

Network traffic can likewise be encrypted to protect its content from forensic

analysis. Cryptographic encapsulation protocols such as SSL and SSH only protect the

content of the traffic. Protecting against traffic analysis requires the use ofintermediaries. Onion Routing (Goldschlag, Reed and Syverson, 1999) combines both

approaches with multiple layers of encryption, so that no intermediary knows both ends

of the communication and the plaintext content .

Program Packers

Packers are commonly used by attackers so that attack tools will not be subject

to reverse engineering or detection by scanning. Packers such as PECompact (Bitsum2006) and Burneye (Vrba 2004) will take a second program, compress and/or encrypt it,

and wrap it with a suitable extractor. Packers can also incorporate active protection

against debugging or reverse engineering techniques. For example, Shiva will exit if its

process is being traced; if the process is not being traced, it will create a second

process, and the two processes will then trace each other, since each process on a

Unix system may only be traced by one other process. (Mehta and Clowes, 2003)

Packed programs that require a password in order to be run can be as strong astheir encryption and password. However, the programs are vulnerable at runtime.

Burndump is a loadable kernel module (LKM) that automatically detects when a

Burneye-protected file is run, waits for the program to be decrypted, and then writes the

raw, unprotected binary to another location (ByteRage 2002). Packed programs are

also vulnerable to static analysis if no password is required (Eagle 2003).

Steganography

Steganography can be used to embed encrypted data in a cover text to avoid

detection. Steghide embeds text in JPEG, MBP, MP3, WAV and AU files (Hetzl 2002).

Hydan exploits redundancy in the x86 instruction set; it can encode roughly 1 byte per

110 (El-Khalil 2004). Stegdetect (Provos 2004) can detect some forms of

steganography.
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StegFS hides encrypted data in the unused blocks of a Linux ext2 file system,

making the data look like a partition in which unused blocks have recently been

overwritten with random bytes using some disk wiping tool (McDonald and Kuhn,

2003).

FreeOTFE and TrueCrypt allow a second encrypted file system to be hidden

within another encrypted file system. The goal of this filesystem-within-a-filesystem is to

allow the users to have a decoy file system with data that is interesting but not overtly

sensitive. A person who is arrested or captured with a laptop encrypted using this

software could then give up the first file system s password, with the hope that the

decoy would be sufficient to satisfy the person s interrogators.

Generic Data Hiding

Data can also be hidden in unallocated or otherwise unreachable locations that

are ignored by the current generation of forensic tools.
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Metasploit s Slack er will hide data within the slack space of FAT or NTFS file

system. FragFS hides data within the NTFS Master File Table. RuneFS (Grugq 2003)

stores data in bad blocks. (Thompson and Monroe, 2006). Waffen FS stores data in the

ext3 journal file (Eckstein and Jahnke 2005). KY FS stores data in directories (Grugq

2003). Data Mule FS stores data in inode reserved space (Grugq 2003). It is also

possible to store information in the unallocated pages of Microsoft Office files.

Information can be stored in the Host Protected Area (HPA) and the Device

Configuration Overlay (DCO) areas of modern ATA hard drives. Data in the HPA and

DCO is not visible to the BIOS or operating system, although it can be extracted with

special tools.
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