INTERNET SECURITY PROBLEMS
A virus is a software program that is capable of replicating with little or no user intervention, and the replicated programs also replicate further. Viruses can piggyback on real programs. For example, a virus may attach itself to a program such as a spreadsheet program. Each time the spreadsheet program runs, the virus runs as well, and it has the opportunity to reproduce by attaching to other programs. The purpose of a virus can be anything from erasing files, formatting your hard drive, to replacing text in your document. Viruses are often disguised as games or images with clever titles such as "Pictures of ME".
E-mail Viruses- An e-mail virus moves around in e-mail messages, and usually replicates itself by automatically mailing itself to the people in the victim's e-mail address book.
Worms- A worm is a virus that spreads by creating duplicates of itself on other drives, systems, or networks. Worms may send copies of themselves to other computers across network connections, through e-mails, through infected web pages, or through instant messages.
How Viruses Spread
When you execute program code that is infected by a virus, the virus code will also run and try to infect other programs, either on the same computer or on other computers connected to it over a network. And the newly infected programs will try to infect yet more programs. When you share a copy of an infected file with other computer users, running the file may also infect their computers; and files from those computers may spread the infection to yet more computers.
For example, if your computer is infected with a boot sector virus, the virus tries to write copies of itself to the system areas of flash drives and hard disks. Then the infected drives may infect other computers that boot from them, and the virus copy on the hard disk and will try to infect still more drives.
Malware, Spyware Adware, Keyloggers and Trojans:
Most people have heard of computer viruses but many have never heard of Malware. Malware has become the largest threat to computer users, surpassing Viruses/Worms. Malware is an all encompassing term for everything (Spyware, Adware and Trojans) besides a straight virus. Spyware was initially developed as a demographic marketing tool. The concept is, when you visit a site the site will send down a piece of Spyware, which is a small program that collects your browsing habits. The Spyware runs in the background taking up resources of computer and slowing it down to a small extent. When it has collected the data it then sends the data back to the originating site. This way the people who run the site can see your browsing/buying habits and target you with junk e-mail (SPAM). Now there are many different types of Malware (1000s), the type just described, others hijack your web browser and change it's look and function, some like viruses can lie dormant and collect your username, password, and credit card information and then when you are on-line transmit them to a web site that collects the information. Besides invading your privacy and stealing your personal information Malware slows down your machine and makes it act strange. As I said earlier a Malware program will slow your machine down to some extent. Now multiply that by 100 or 1000 pieces of Malware running and your computer comes to a complete halt. If you think 1000 pieces of Malware running on one machine is a stretch I have cleaned machines with over 17,000 traces of Malware running (but the computer was not running very well).
Indications Of Malware Infection: The following are some of the symptoms of Malware infection:
- Poor system performance, especially while browsing the Internet.
- The computer stops responding more frequently.
- Computer takes longer to open the Windows desktop.
- Browser closes unexpectedly or stops responding.
- Performing a search from a search page provides results on a different site.
- Clicking a link does nothing or goes to a non-related Web site.
- Browser home page changes and may not be able to be reset.
- Pop-up advertising windows appear when the browser is not open or over Web pages that do not normally have pop-ups.
- Additional toolbars are added to the browser.
- Web pages are automatically added to list of favorites.
- Desktop icons are automatically added to the desktop.
- Large unexpected bills.
Ransomware has been making headlines in the last couple of years. The method of infection is identical to the way most malware is transmitted these days via e-mail. Typically an e-mail is sent to somebody (normally a secretary) in a targeted company with an iinnocuous attachment. It often looks like a typical PDF document. The unaware person opens the infected attachment and nothing happens, or so it seems. In the background the infection is migrating all through the company's network looking for and infecting all the data files. After a given time the infection is triggered and all of the infected data files are encrypted and totally useless. Then the bad guys contact the company and demand a large ransom to decrypt the company files. If it is not paid they don't decrypt the files and all the company files are useless forever. The encryption is very sophisticated and it would take a group of super computers over 4 million years to crack the code and decrypt the files. The bad guys are constantly looking for new ways to ply their trade. The only sure way to mitigate the damage is have a regular backup of all of your critical data.
How to Avoid Viruses and Malware or mitigate their impact
- Install Anti-Virus and Anti-Malware software, update it regularly, and use it regularly.
- Do regular backups. If you contract a virus/malware it may be the only way to recover your data. Ideally, you should backup your entire system on a regular basis, however if this is not practical, at least backup files that you can't afford to lose or that would be difficult to replace: documents, bookmark files, address books, important e-mails, pictures, etc.
- When possible, avoid e-mail attachments both when sending and receiving e-mail.
- Never open e-mail attachments with the file extensions EXE, COM, BAT, VBS, SHS, PIF. These extensions are almost never used in normal attachments but they are frequently used by viruses and worms and other malware.
- Never open attachments with double file extensions such as NAME.BMP.EXE or NAME.TXT.VBS.
- If you feel that an e-mail you get from a friend is strange (if it is a foreign language or it just says odd things) double check with the friend before opening any attachments.
- When you receive e-mail advertisements or unsolicited e-mail, do not open attachments.
- Avoid attachments with sexual file names.
- Do not trust the icons of attachment file. malware often uses executable files which have an icon resembling icons of picture, text, PDF, or archive files to fool the user.
- Avoid using flash drives to exchange information between computers.