NWA-PCUG Newsletter Article, January 2005
Do You Know How Safe Your Credit Card Number Is?
by S. Jack Lewtschuk, Monterey Bay Users Group – PC,
California Columnist & Immediate Past President
November 2004 mbug-pc newsletter

How many times have you typed your credit card number or password into your computer? Any idea what happens to it?

When you type in a password, it is stored in random access memory (RAM), where it is held temporarily until other data overwrites it or the computer is turned off. But every so often, the computer copies the contents of its RAM onto hard disk, where it is easy prey for a hacker, who can read it directly or design a worm to e-mail it back. The longer sensitive data is in RAM, the more likely it is to be copied onto the disk, where it stays until it is overwritten – which might not happen for years.

On the other hand, do you know what happens to your credit card number after you hand your card to a clerk in a store or server in a restaurant? He/she has your number and your signature.

Are you paranoid yet?

Keep a record of your credit cards and other contents of your wallet. Place the contents of your wallet on a photocopy machine or scanner; copy both sides of each license, credit card, etc. You will know what you had in your wallet and all of the account numbers and phone numbers to call to report the theft and cancel the cards. Keep the photocopy in a safe place.

If you do lose your wallet, don’t forget to call these numbers to report it:

    Equifax 800.525.6285
    Experian (formerly TRW) 888.397.3742
    Trans Union 800.680.7289
    Social Administration Fraud Line 800.269.0271
    Your local police department to file a theft report


By the way, have you heard the idea that it is best not to sign the back of your credit cards? That instead of signing, you can print the words: “SEE ID” or “ASK FOR PHOTO ID?”

Here is what major credit card fraud departments had to say:

    MasterCard – To not sign your card is an urban legend that sounds sensible, but is not a good idea.
    American Express – We have warned merchants not to accept your credit cards if they aren’t signed.
    VISA – They agree with the other credit card companies and said that merchants are instructed not to finish the transaction until you sign the back of your card.

So, the idea of not signing the back of your credit card is an example of a very popular urban legend that is false. Sign your credit cards immediately when you receive them.

There is no restriction against any non-profit group using this article as long as it is kept in context with proper credit given the author. The Editorial Committee of the Association of Personal Computer User Groups (APCUG), an international organization of which this group is a member, brings this article to you.

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