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A cookie is typically a short string. If it contains sensitive information, that information should be encrypted. Sensitive information includes user names, passwords, credit card numbers, social security numbers, and any other personally identifiable information about the user. For more details about managing passwords, see MSC62-J. Store passwords using a hash function. For more information about securing the memory that holds sensitive information, see MSC59-J. Limit the lifetime of sensitive data.
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