|
Viruses Knowledge
A computer virus is a computer program designed to enter your computer system and tamper with your files illegally. Once the program containing the virus is opened, the virus is activated and it can infect important files on your computer system. These infected files will be corrupted and the victim’s computer system may be caused to crash. Some viruses automatically duplicate themselves and disseminate to other computer systems that are connected to yours, just similar to a physical virus that moves from one victim to others.
Besides, specific viruses can spread to other computers by infecting files on a network file system or a file system that is accessed by another computer. Viruses are sometimes confused with computer worms and Trojan horses. A worm can spread itself to other computers without needing to be transferred as part of a host, and a Trojan horse is a file that appears harmless until executed by the computer user, by its remote host or by any designed means.
Some viruses are programmed to damage the computer system by corrupting or deleting files (or programs) or even formatting hard disks. Others are designed to duplicate themselves and make their presence known by presenting text and visual messages. They take up computer memory, cause erratic behavior and may lead to system crashes and data loss.
The computer virus history emerged in the late 1980s as personal computers, e-mails and the Internet became popular. People stored data files and application programs on portable floppy disks and the network for sharing and transmission while viruses were hidden in these files and programs and disseminated to other computer systems.
Today viruses can spread to other computer systems in the following ways and occasions.
-
Users access infected files on a network device from their own computers.
-
An infected removable storage media is attached to the computer.
-
An infected email is opened by the user or executed by the email system.
-
An infected program or file is downloaded from the Internet to the computer.
Hackers Information
A Hacker is a general term in computing that refers to a computer programmer who takes advantage of the weaknesses, flaws and faults of the computer systems in order to gain illegal access to the system without user’s or her knowledge and consent. Hackers can use hacker tools and programs to penetrate and access remote computers. After accessing the computer, hackers can steal the wanted sensitive data and information, delete files, manipulate the system and monitor user’s behavior.
In general, computers can be illegally hacked when users perform the following activities.
-
Open the email attachments that contain hacker programs
-
Communicate through MSN, Yahoo and other instant messenger programs
-
Share infected music, video and image files
-
Download or open files that contain hacker programs
-
Copy infected files from CDs, DVDs, USB or other storages devices
-
Access to the Internet or any network through wireless device without proper security settings
-
Click on deceptive links and pop-ups of some attacking websites
-
Type their sensitive data on fraudulent websites
Hackers can also use special software or hardware tools to launch attacks on users remotely and directly even they do not perform any specific activities. The DoS (Denial of Service), nuker and flooder tools, etc are commonly used by hackers to execute remote and direct attacks to specified computer systems. DoS programs attack web servers by sending many requests to the specified computer systems. The attacked system may deny the service and even crash under excessive requests. Hackers can use nuker tools to crash attacked computer systems by sending specially coded or phrased requests. These requests exploit vulnerabilities in application programs and operating systems to cause fatal errors. Flooder tools are sometimes used by hackers to flood data channels with useless packets and emails.
Other Threats There are many other threats that can damage your computer systems or sneak your sensitive data and information. The most common threats include worms, Trojans, macros, spyware, adware, jokes, etc. Computer users are recommended to install appropriate anti-virus and security solutions on their systems or networks to avoid these threats. Most of these anti-virus and security solutions provide frequent updates to protect users from the newly found threats. Therefore users are advised to perform these updates periodically or set these solutions to perform automatic updates (if any).
|
