More and more we are seeing hackers out there exploit email addresses and webmail logins using dictionary style attacks. A dictionary attack is a technique for defeating a cipher or authentication mechanism by trying to determine its decryption key or passphrase by searching a large number of possibilities. In contrast with a brute force attack, where all possibilities are searched through exhaustively, a dictionary attack only tries possibilities which are most likely to succeed, typically derived from a list of words in a dictionary. Generally, dictionary attacks succeed because many people have a tendency to choose passwords which are short (7 characters or less), single words in a dictionary, or are simple variations that are easy to predict, such as appending a single digit to a word.

Use
Dictionary attacks may be applied in two main situations:

1. in cryptanalysis, in trying to determine the decryption key for a given piece of ciphertext;
2. in computer security, in trying to circumvent an authentication mechanism for accessing a computer system by guessing passwords.

Spammers often use a form of dictionary attack, sometimes known as a Directory Harvest Attack, for e-mail address harvesting. For example, a spammer may try sending messages to adam@example.com, barbara@example.com, carl@example.com, etc. Any addresses to which messages are delivered, as opposed to being bounced back, can be added to the spammer's list of known-valid addresses.

Having a Strong password can divert these attempts and keep your data safe. A strong password is sufficiently long, random, or otherwise producible only by the user who chose it, such that successfully guessing it will require more time than the password cracker is willing to use guessing it. The length of time deemed to be too long will vary with the attacker, the attacker's resources, the ease with which a password can be tried, and the value of the password to the attacker. A student's password might not be worth more than a few seconds of computer time, while a password controlling access to a large bank's electronic money transfer system might be worth many weeks of computer time.

Examples of stronger passwords include:

t3wahSetyeT4 -- case-sensitive and alphanumerics
4pRte!ai@3 -- case-sensitive, alphanumerical, punctuation and one "special" character
MoOoOfIn245679 -- case-sensitive, alphanumerical
1382465304H -- a string of numerals ending with a letter
Tpftcits4Utg! -- A mixture of varying-case letters, one numeral, and punctuation. It is memorable as an initialism of "The password for this computer is too strong for you to guess!"

If you are in doubt that your passwords are safe enough, you can ask IT or Hosting provider or simply use the above as a guideline to creating your passwords. There are also many password generators on the market that will help you create Strong passwords to keep you safe.


Shannon Cox has empowered companies by providing internet consulting, web development, web design, branding, system integration and many other business consulting solutions since 1995. Currently, he owns and operates www.argonhosting.com providing quality web hosting, reseller web hosting and site building solutions.