Hello friendz....
Now it's time to learn some facts about security threat's.Threats can be divided in to two categories.
First those need a host program and other which are independent.The former are essentially fragments of programs that can't exists independently of some actual application program,utility,or system program.The latter are self-contained programs that can be scheduled and run by the operating system(OS).TRAP DOORS -
A trap door is a secret entry point in to a program that allows someone that is aware of the trapdoor to gain access without going through the usually security access procedures.Trap doors have been used legitimately for many years by programmers to debug and test program's.This is done when the programmer is developing an application that has an authentication procedure, or a long setup,requiring the user to enter many different values to run the application.To debug the program,the developer may wish to gain special privileges or to avoid all necessary setup and authentication.The programer also want to ensure that there is a method of activating the program should something be wrong with the authentication procedure that is being built in to the application.The trap door is a code that recognizes some special sequence of input or is triggered by being run from a certain user ID or by an unlikely sequence of event.
Trap doors becomes threats when they are used by unscrupulous programmers to gain unauthorized access.It is difficult to implement operating system(OS) controls for trap doors.
LOGIC BOMB -
A logic bomb is a piece of code intentionally inserted into a software system that will set off a malicious function when specified conditions are met. For example, a programmer may hide a piece of code that starts deleting files (such as a sala database triggers), should they ever be terminated from the company.
Software that is inherently malicious, such as viruses and worms, often contain logic bombs that execute a certain payloads at a pre-defined time or when some other condition is met. This technique can be used by a virus or worm to gain momentum and spread before being noticed. Many viruses attack their host systems on specific dates, such as Friday the 13th or April fool's day. Trojans that activate on certain dates are often called "time bombs".
To be considered a logic bomb, the payload should be unwanted and unknown to the user of the software. As an example, trial programs with code that disables certain functionality after a set time are not normally regarded as logic bombs.
TROJAN HORSE -
A Trojan horse, or Trojan, is software that appears to perform a desirable function for the user prior to run or install, but (perhaps in addition to the expected function) steals information or harms the system.The term is derived from the Trojan Horse story in Greek mythology.
Trojan horses in this way require interaction with a hacker to fulfill their purpose, though the hacker need not be the individual responsible for distributing the Trojan horse. It is possible for individual hackers to scan computers on a network using a port scanner in the hope of finding one with a malicious Trojan horse installed, which the hacker can then use to control the target computer.A recent innovation in Trojan horse code takes advantage of a security flaw in older versions of IE explorer and Google Chrome to use the host computer as an anonymizer proxy to effectively hide internet usage. The hacker is able to view internet sites while the tracking cookies, internet history, and any IP logging are maintained on the host computer. The host computer may or may not show the internet history of the sites viewed using the computer as a proxy. The first generation of anonymizer Trojan horses tended to leave their tracks in the page view histories of the host computer. Newer generations of the Trojan horse tend to "cover" their tracks more efficiently. Several versions of Slavebot have been widely circulated in the US and Europe and are the most widely distributed examples of this type of Trojan horse.
ZOMBIE -
zombie is a computer connected to the Internet that has been compromised by a cracker, computer virus or trojan horse and can be used to perform malicious tasks of one sort or another under remote direction. Botnets of zombie computers are often used to spread e-mail spam and launch denial-of-service attacks. Most owners of zombie computers are unaware that their system is being used in this way. Because the owner tends to be unaware, these computers are metaphorically compared to zombies.
For similar reasons zombies are also used to commit click fraud against sites displaying pay per click advertising. Others can host phishing or money mule recruiting websites.
WORM -
A computer worm is a self-replicating malware computer program, which uses a computer network to send copies of itself to other nodes (computers on the network) and it may do so without any user intervention. This is due to security shortcomings on the target computer. Unlike a computer virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, even if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer.
VIRUS -
A computer virus is a computer program that can replicate itself and spread from one computer to another. The term "virus" is also commonly but erroneously used to refer to other types of malware, including but not limited to adware and spyware programs that do not have the reproductive ability. A true virus can spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive.
Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by another computer.As stated above, the term "computer virus" is sometimes used as a catch-all phrase to include all types of malware, even those that do not have the reproductive ability. Malware includes computer viruses, computer worms, Trojan horses, most rootkits, spyware, dishonest adware and other malicious and unwanted software, including true viruses. Viruses are sometimes confused with worms and Trojan horses, which are technically different. A worm can exploit security vulnerabilities to spread itself automatically to other computers through networks, while a Trojan horse is a program that appears harmless but hides malicious functions. Worms and Trojan horses, like viruses, may harm a computer system's data or performance. Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious or simply do nothing to call attention to themselves. Some viruses do nothing beyond reproducing themselves.
MALICIOUS PROGRAMS
Need host program .Independent
1.Trap Doors 1.Worm
2.Logic Bombs 2.Zombie
3.Trojan Horse
4.Viruses
That's all for today....
See u soon friend's....
SUNIL SINGH
