There are a number of emails going out notifying people their credit cards are being blocked. The problem with these emails? They are not from the credit card companies but from enterprising criminals trying to get the unsuspecting to open email attachments containing malware.
The recipients of this email are baited with statements about large sums being applied to the card and to see additional information to open the attached file. If you do try to open the file you are actually launching a malware attack on your computer.
Anytime you receive an email notification about a credit card do not trust any attachments, links or phone numbers contained in the email. Dial the phone number listed on the back of the card or from your statement and verify the email is a legitimate correspondence from your card provider.