What
are Forensic Computer Examinations?
Why
should you consider using forensic computer examinations and a trained
forensic examiner?
If
the case or issue at hand is important,
you should use a trained, experienced forensic
computer examiner. Whether you us
or another sufficiently trained and experienced
examiner, is your decision. Any
examination of a computer and the data contained on the media conducted
by an untrained person, could result in:
-
Not
finding all of the data
-
Not
finding or recovering deleted data
-
Not
recovering password protected data
-
Not
finding or recovering hidden data
-
A
loss or corruption of data
-
The
destruction of data
-
A
total crash of the computer
-
The
inadmissibility of the data
-
A
valid lawsuit
Many
software applications keep temporary records, temporary documents and other
temporary data that the user is not aware of, and therefore, the
user does
not delete the data, password protect the data or otherwise try to hide the
data. This data can normally
be quickly located and accessed by trained, experienced forensic examiners.
Windows
keeps a swap file that is used when memory resources are low.
This is a dynamic file that grows with use. This swap file can hold
complete files or other data that can significantly help a case.
Web
browsers keep a number of temporary files, including cache and history
files that tell where and when web sites were visited and keeps copies
of files that were viewed. These temporary files can be accessed,
viewed and copied. The data contained in these files can be very
valuable to a case or investigation.
The
most common method used to hide data is to delete files or format
the drive or diskette. Deleting a file or formatting a drive or diskette,
does not necessarily destroy the data. An experienced forensic examiner can recover
the deleted data and draw expert conclusions as to when, how or why
the data was deleted or removed from the media.
Frequently
recovering deleted or formatted data and showing which particular
files were deleted or removed is a good indication of culpability or valuable
insight into what the person was trying to do at the time of the deletions.
Determining
dates and times of deletion or formatting frequently coincides with
actions taken by employers and law enforcement, i.e. the employee
formats his hard disk drive one hour after being accused of selling or
using company sensitive data.
Data
that is password protected is usually data that the user does not
want others to see or access. Password protected data frequently contains
relevant information to the investigation or inquiry at hand. An experienced
forensic examiner has the knowledge and equipment to unlock passwords and
access the data.
It
is relatively simple to alter an operating system or it's internal
commands (i.e., DIR, COPY, TYPE, etc.) to do something other than Boot
or display the Directory listing, Copy files or Type files.
Alterations
to the operating system or internal commands are usually made by persons
who want to conceal or destroy data that they do not want others
to see. This is usually the kind of data that will be important to an investigation
or inquiry.
Simply
booting a target or suspect's machine will cause the alteration of
certain operating system files. Although this normally will
not cause the alteration of user created files. This will, arguably,
cause the alteration of the original media.
Simply
booting a target or suspect's machine may cause the loss or destruction
of data or the activation of
destructive processes set up by the suspect to occur. Typing
an internal command such as, DIR to see what's on the machine, could activate
destructive processes. Any or all of the data on the machine could be completely
destroyed and the operating system could be made inoperative.
Valid
lawsuits could follow if an untrained person looking at the system
crashed the machine or destroyed critical data. An experienced
forensic examiner will not fall into this sort of trap.
It
is also relatively simple to hide files that normal DOS/WINDOWS
commands, such as, DIR and other commands cannot find. The hidden file
simply will not be displayed, and its contents will not be found or examined.
An untrained person may not know if a file that appears to contain no
data,
is corrupted or encrypted or actually contains no data. An untrained person
may not know that a file that appears normal, actually contains hidden
data.
Data
can be hidden or located in many places on a computer hard disk drive or
other media. Untrained persons probably will probably not find the data.
The
use of an untrained person could cause the inadvertent destruction of data,
overlook deleted, hidden or encrypted data and could cause inadvertent
writes back to and alter the original media.
Even
if the untrained person found relevant data, the data will probably not
be legally admissible or unusable. This is because of the untrained
person's lack of forensic training and credentials, the use of methods that
were not forensically sound and their lack of understanding of the technical
issues
involved.
Law
enforcement agencies have been trained in and have used forensic computer
examinations for a number of years. Law enforcement agencies
have court proven expertise in computer forensics.
You, your company, your firm or your agency can now benefit from our law
enforcement training and our considerable experience and expertise.
|