How Secure is Cookie

[Anon]

Hi,

I'm wondering if it is possible for users to change the cookie contains stored in their own computer?

I was thinking of utilizing cookie to be used as data storage for shopping cart. Suppose if it is possible to change/alter the cookie, then it's possible for user to change the contains of the shopping cart which i dont want.

Any clues???

[yelvington]

Cookies are not secure. If you really want security, use a secure connection for the overall transaction and store persistent variables in PHP sessions using a secure storage system (not /tmp on a shared host).