14-06-2012, 03:53 PM
Seminar on Computer Security - Hackers
Computer Security - Hackers.ppt (Size: 185 KB / Downloads: 96)
Crisis
Internet has grown very fast and security has lagged behind.
Legions of hackers have emerged as impedance to entering the hackers club is low.
It is hard to trace the perpetrator of cyber attacks since the real identities are camouflaged
It is very hard to track down people because of the ubiquity of the network.
Large scale failures of internet can have a catastrophic impact on the economy which relies heavily on electronic transactions
Computer Crime – The Beginning
In 1988 a "worm program" written by a college student shut down about 10 percent of computers connected to the Internet. This was the beginning of the era of cyber attacks.
Today we have about 10,000 incidents of cyber attacks which are reported and the number grows.
Computer Crime - 1994
A 16-year-old music student called Richard Pryce, better known by the hacker alias Datastream Cowboy, is arrested and charged with breaking into hundreds of computers including those at the Griffiths Air Force base, Nasa and the Korean Atomic Research Institute. His online mentor, "Kuji", is never found.
Also this year, a group directed by Russian hackers broke into the computers of Citibank and transferred more than $10 million from customers' accounts. Eventually, Citibank recovered all but $400,000 of the pilfered money.
Spoofing
Definition:
An attacker alters his identity so that some one thinks he is some one else
Email, User ID, IP Address, …
Attacker exploits trust relation between user and networked machines to gain access to machines
Types of Spoofing:
IP Spoofing:
Email Spoofing
Web Spoofing
Email Spoofing
Definition:
Attacker sends messages masquerading as some one else
What can be the repercussions?
Types of Email Spoofing:
Create an account with similar email address
Sanjaygoel[at]yahoo.com: A message from this account can perplex the students
Modify a mail client
Attacker can put in any return address he wants to in the mail he sends
Telnet to port 25
Most mail servers use port 25 for SMTP. Attacker logs on to this port and composes a message for the user.
Web Spoofing
Basic
Attacker registers a web address matching an entity e.g. votebush.com, geproducts.com, gesucks.com
Man-in-the-Middle Attack
Attacker acts as a proxy between the web server and the client
Attacker has to compromise the router or a node through which the relevant traffic flows
URL Rewriting
Attacker redirects web traffic to another site that is controlled by the attacker
Attacker writes his own web site address before the legitimate link
Tracking State
When a user logs on to a site a persistent authentication is maintained
This authentication can be stolen for masquerading as the user .