Q:

Is it safe to tell credit card number to bank employee over a phone?

Recently, I got a new credit card via post. To activate it, it is required to call to the bank (phone number is attached to the card) and confirm, that card was received. For activation purposes, the bank employee asks me to provide full card number, as well as my name/address/etc.
However, I do not use phone banking so often, and I was not sure if it is safe to tell my card number over phone.
So, are there any security risks of doing this (except Man-In-The-Middle, listening to my phone communication)?

A:

If you consider how credit cards are used there is no increased security risk associated with providing the bank employee with the card number and your name and address.
For example if you use the card for mail order purchases you will provide the same detail, but also the CVV code and expiry date a greater level of risk...but this is how they are intended to be used!
Similarly for any 'in-person' transactions, often the retailer will have full access to all the details from the card, albeit normally without address details.
Given that you are phoning the bank, by implication the person you are providing the details to is trusted by the bank...for the vast majority of subsequent card use scenarios there will not be as much trust in the person you provide the information to.
If the phone call requires you to 'authenticate' using a telephone banking password or phrase of some description, this can help to ensure that someone who has intercepted your post and stolen the newly issued card cannot activate it and use it.

A:

As long as you called them, at a phone number on the card or from your bank 
statement, it sounds standard to me. 
The hazard would be if someone called you claiming to be a bank employee, or
you got the phone number you called from some untrusted source, such as a
piece of email or a random snail mail that appeared to be from the bank.

