How hackers break into your PC

Every computer has an IP (Internet Protocol) address. A DSL or cable modem connection keeps the IP address ‘always on’. A dial-up account’s IP address is turned off by the service provider after a certain amount of inactivity. Dial-up accounts get a different IP address each time they are on. Common methods for finding your IP address are through chatrooms, looking up domain names on a domain name registrar site, or running programs that can create a log of all valid IP addresses. In a chatroom, all a hacker has to do is right click on your chat ID and get your IP address. A domain registrar can yield a website’s employees’ names, phone numbers, fax numbers, physical addresses and IP addresses. In ‘social engineering’ a hacker verbally chats you up and gets your IP address and other important information. The hacking With your IP address, a hacker can send programs to your PC to test your system for vulnerabilities. He can find bugs, or holes in software. File- and print-sharing options allow him to access your hard drive, load any program on the drive and delete/change any file on your PC.
He may use ‘Trojans’, which pretend to do useful tasks--like playing a video or greeting--but actually help him access info on your comp and/or even take it over. Programs that allow the hacker ‘backdoor’ entry to your comp are commonly available. They are used daily and legitimately by systems administrators for remote systems. Hackers change the names of their programs to make them look like legitimate system programs. Or they create a hidden folder on your comp to keep programs. The most common way that viruses are spread is through e-mail. Usually, the virus is not in the e-mail itself, but an attachment. Cracking passwords Hackers use programs to crack passwords. Even a password-protected computer can be broken into and other passwords then cracked. A cracker dictionary has common computer terms and phrases, names, slang and jargon, easily typed key sequences (like ‘qwerty’), and phrases you might commonly use as a password. Programs to crack passwords are handed out with copies of these dictionaries. A common method for cracking passwords is to get a copy of a system’s password file. It lists all encrypted passwords on the system.
Security breached A hacker can steal and delete files, load dangerous programs on your PC, involve you in computer crime. He can get your home, office or bank passwords. A hacker can see your screen as you see it, watch every move of your mouse, see every word you type Proxy problems. Often, the hacker is not interested in the hacked system. He just wants to hack into larger systems or send e-mails. A hacker can load a program onto hundreds of hacked PCs and then direct the PCs to bomb a particular firm’s server with junk mail or problem messages. Securing your computer Turn off your comp when not using it Use a firewall and anti-virus. Turn off file and print sharing. Be up-to-date. Hackers count on the public’s ignorance. Specific measures Don’t visit chat rooms unless they are closed and you know the administrator. Almost never open an attachment that ends in .DLL or .EXE, even if the email is from your best friend. The only time you can open such attachments is if you know what’s in them. To outwit script-based viruses, ask an expert how you can open scripts in Notepad (or Wordpad). Then get someone who knows Visual Basic to look at it. If you’re not on your PC, but see its modem lights flash, a hacker could be testing for vulnerabilities. Password protection A good password is easily remembered, but not easily guessable. It should be kept a secret, never written down, never saved in a file. When a website asks if a password should be saved, say no. A password must have at least six or more letters, numbers or punctuations. The letters should be capitals and lowercase. It should not have four or more letters found consecutively in the dictionary. Reversing the letters won’t help. Legal means The government could make it mandatory for PC and laptop owners and ISPs to use security measures.
source:TOI