2. the term hacker simply referred to an adept
computer user, and gurus still use the term to
refer to themselves in that original sense.
when breaking into computer systems
(technically known as cracking) became popular,
the media used the hacker to refer only to
computer criminals
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 2
3. Hacking is illegal. Title 18, United States Code,
Section 1030, by Congress in 1984
the perpetrator must “knowingly” commit the
crime
notification that unauthorized access is illegal be
posted
For a computer-related crime to become a
federal crime, the attacker must be shown to
have caused at least $5,000 worth of damage.
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 3
4. 2004 CANSPAM Act specifically criminalizes the
transmission of unsolicited commercial e-mail
without an existing business relationship.
Before that, spamming was not a crime!
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 4
5. Because of the time it takes, there are only two
serious types of hackers:
› the underemployed and
› those hackers being paid by someone to hack.
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 5
6. Hackers fall quite specifically into these
categories, in order of increasing threat:
› Security experts
› Script kiddies
› Underemployed adults
› Ideological hackers
› Criminal hackers
› Corporate spies
› Disgruntled employees
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 6
7. Most security experts are capable of hacking but
decline to do so for moral or economic reasons.
Computer security experts have found that
there’s more money in preventing hacking than
in perpetrating it
hundreds of former hackers now consult
independently as security experts to medium-
sized businesses.
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 7
8. Script kiddies are students who hack
These hackers may use their own computers, or
(especially at colleges) they may use the more
powerful resources of the school to perpetrate
their hacks.
joyride through cyberspace looking for targets of
opportunity
concerned mostly with impressing their peers
and not getting caught.
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 8
9. in most instances, you’ll never know they were
there unless you have software that detects
unusual activity or unless they make a mistake.
These hackers constitute about 90 percent of
the total manual hacking activity on the Internet.
They use the tools produced by others,
script kiddies hack primarily to get free stuff
They share pirated software and serial numbers
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 9
10. Underemployed adults are former script kiddies
either dropped out of school or failed to achieve
full-time employment and family commitments
Many of the tools script kiddies use are created
by these adult hackers
Adult hackers often create the “crackz” applied
by other hackers to unlock commercial software.
This group also writes the majority of the
software viruses.
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 10
11. Ideological hackers are those who hack to further
some political purpose.
Since the year 2000, ideological hacking has gone
from just a few verified cases to an information war
They deface websites or perpetrate DoS attacks
against their ideological enemies.
looking for mass media coverage of their exploits
have the implicit support of their home government
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 11
12. Criminal hackers hack for revenge, to perpetrate
theft, or for the sheer satisfaction of causing
damage.
exceedingly rare because the intelligence
required to hack usually also provides ample
opportunity for the individual to find some
socially acceptable means of support
little risk to institutions that do not deal in large
volumes of computer-based financial
transactions
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 12
13. very rare because it’s extremely costly and
legally very risky to employ illegal hacking tactics
against competing companies
Many high technology businesses are young and
naïve about security
Nearly all high-level military spy cases involve
individuals who have incredible access to
information but as public servants don’t make
much money
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 13
14. Disgruntled employees are the most dangerous
—and most likely—security problem of all
Attacks range from the complex (a network
administrator who spends time reading other
people’s e-mail) to the simple (a frustrated clerk
who takes a fire axe to your database server).
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 14
15. There are only four ways for a hacker to access
your network:
1. By connecting over the Internet
2. By using a computer on your network directly
3. By dialing in via a Remote Access Service (RAS)
server
4. By connecting via a nonsecure wireless network
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 15
16. Solving the direct intrusion problem is easy:
Employ strong physical security at your premises
treat any cable or connection that leaves the
building as a security concern.
putting firewalls between your WAN links and
your internal network or behind wireless links
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 16
17. Put your RAS servers outside your firewall in the
public security zone,
force legitimate users to authenticate with your
firewall first to gain access to private network
resources.
Allow no device to answer a telephone line
behind your firewall.
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 17
18. 802.11b came with a much-touted built-in
encryption scheme called the Wired-Equivalent
Privacy (WEP) that promised to allow secure
networking with the same security as wired
networks have.
It sounded great.
Too bad it took less than 11 hours for security
experts to hack it
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 18
19. newer 128-bit WEP service is more secure, but it
should still not be considered actually equivalent
to wired security
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 19
20. Target selection
Information gathering
Attack
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 20
21. To pass this stage, some vector of attack must
be available, so the machine must have either
advertised its presence or have been found
through some search activity.
› DNS Look-up
› Network Address Scanning
› Port Address Scanning
› Service Scanning
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 21
22. › SNMP Data gathering
› Architecture probes
› Directory service look-up
Rushdi Shams, Lecturer, Dept of CSE, KUET, Bangladesh 22