Direct Attack of computer

When a computer is the object of an attack, it is the entity being attacked. There are two types of attacks: direct attacks and indirect attacks.

A direct attack is when a hacker uses his personal computer to break into a system. A direct attack would take the form of hacking into computer system and rewriting or stealing information. Some recent examples have that hackers operate for political purposes.

Direct attacks originate from the threat itself. Indirect attacks originate from a system or resource that itself has been attacked and is malfunctioning or working under the control of a threat.

A computer can, therefore, be both the subject and object of an attack when, for example, it is first the object of an attack and then compromised and used to attack another systems, at which point it becomes the subject of an attack.

The target of an attack is always the protected information. An object of direct attack is the object whose analysis or usage will allow successful unauthorized access to protected information.
Direct Attack of computer

Computer Attack

Denial of Service Attacks
A denial of service attack results when access to computer or network resource is intentionally blocked or degraded as a result of malicious action taken by another user.

These attacks do not necessarily damage data directly or permanently (although they could), but they intentionally compromise the availability of the resources.

These types of attacks tend to affect the availability of computer systems for legitimate usage. These forms of attacks can include e-mail bomb attacks, sending thousands of e-mails to a particular computer system until that system crash, the software required to carry out denial of service attacks in widely available on the internet.

Another commonly used denial of service attack is the Ping O’ Death. The Ping O’ Death can crash or reboot a computer by sending a ‘ping’ message of greater than 65,536 bytes the default size is 64 bytes. Router updates have nearly eliminated these problems.

Denial of service attacks could be very effective against an Internet based company, since they rely on on-line connectivity. These sorts of attacks could easily disrupt electronic commerce on-line mechanisms.

Direct Attack 

A direct attack would take the form of hacking into computer system and rewriting or stealing information. Some recent examples have that hackers operate for political purposes.

Another method of hacking is more concerned with attacking computers files and destroying, modifying or extracting data. These types of hacking attacks may be less apparent to organizations, as they may not realize they have a victim.

Cyber terrorists would use hacking as an extensive part of their ‘attack strategy’ against electronic commerce. By hacking Web sites, cyber terrorists will gain a global audience for their political message and they will also be able to discredit the security of the companies using the on-line service.

It should be remembered that hackers are available for hire on the open market and therefore their service can be easily acquired.

By actually hacking the data contained within the system, sales can be disrupted, or data altered. This would help to harm the organization’s effectiveness or allow fraud to take place.
Computer Attack

Computer Viruses

One of the most destructive examples of computer crime involves the creation of computer viruses or worms. Virus is the more popular term but, technically, a virus is a program code that cannot work without being inserted into another program.

A worm is a distinct program that can run unaided. In either case, these programs copy annoying or destructive routines into the networked computer systems of anyone who accesses computers infected with the virus or who uses copies of disks taken from infected computer.

Thus, a computer virus or worm can spread destruction among many users. Though they sometimes display only humorous messages, they more often destroy the contents of memory, hard disks, and other storage devices. Copy routines in the virus or worms spread the virus and destroy the data and software of many computer users.

Computer viruses typically enter a computer system through E-mail and file attachments via the Internet and online services, or through illegal or borrowed copies of software. Copies of shareware software downloaded from the internet can be another source of viruses.

A virus usually copies itself into the files of a computer’s operating system. Then virus spreads to the main memory and copies itself onto the computer’s hard dick and any inserted disks.

The virus spreads to other computers trhough E-mail, file transfer, other telecommunications activities, or disks from infected computers. Thus, as a good practice, avoid using software from questionable sources without checking for viruses.

Also need to use regularly antivirus programs that can help diagnose and remove computer viruses from infected files on hard disk.
Computer Viruses