Types of Attacks

There are too many types, methods and mechanisms of attack to provide a comprehensive description of all of them. New attack techniques and exploits are constantly being developed and discovered.
Ultimately all attacks are originated by people with a motivation to steal, cause vandalism, prove themselves to be elite hackers, or just for the thrill it gives them. Most attacks are actually performed by automated tools that such people release on the Internet.
• Virus

Computer viruses have a long history. A virus attempts to install itself on a user's system and to spread directly to other files on that system with the aim that these infected files will be transferred to another machine. The payload of a virus can range from 'comical' pranks to destruction of the system itself.
A virus relies on users to spread by sharing infected files either directly or via email. Once launched, a virus is completely independent of its creator.
Although the most common threat to security, the traditional virus does not attack other systems directly and so is unlikely to be detected by KFSensor.

• Worm

A worm is very similar to a virus. The key difference is that a worm attempts to propagate itself without any user involvement. It typically scans other computers for vulnerabilities which it is designed to exploit. When such a machine is identified, the worm will attack that machine, copying over its files and installing itself, so that the process can continue.
KFSensor excels at detecting worms as they scan and attempt to attack very large numbers of systems at random.

• Trojan

Trojans take their name from the trojan horse of Greek mythology.
Computer trojans work in the same way. A game, screen saver or cracked piece of commercial software is given to a victim. The software may appear to work as normal, but its real purpose is to deliver a payload, such as a virus or a root kit.

Denial of Service (DoS)

A denial of service attack is a simple, but often extremely effective, attack that is difficult, if not impossible, to prevent. The goal of a denial of service attack is to deny access to your particular services, effectively preventing your organization from operating. A denial of service could be launched against any part of your Internet connectivity and network infrastructure.

Mail Bombing

Another type of Denial of Service attack can be caused by mail bombing, in which an attacker targets your email system by sending overly large email messages to users such as postmaster or Webmaster. This not only affects your Internet connection bandwidth, but also your mail server's capability to handle other email. An attack such as this could easily fill up your mail server's mail store drive, preventing you from sending or receiving new email.