[{"_id":{"$oid":"6241d974a7382732093700d1"},"userdata":{"Name":"SomeName","Surname":"SomeSurname","Email":"someEmail@gmail.com","Adress":{"Ulica":"Street","NumerDomu":"2137","NumerMieszkania":"2137","KodPocztowy":"22222","Miasto":"Warsaw"}},"username":"usrnmatest","password":"$2a$11$kLDNbOmg2Ju4jl4o7mcyyuThuE5ZN1xd4VB10TYI/xPtQO.zM828a","cards":[{"issuer":"Visa","cardNumber":"46556456445564","expiryMonth":"12","expiryYear":"2027","CVV":"223","name":"Pablo","address":"Krynica 21","country":"Poland","zipcode":"33-380"},{"issuer":"MasterCard","cardNumber":"2178811445564","expiryMonth":"10","expiryYear":"2032","CVV":"114","name":"Some Data","address":"ul.Moskiewskiego 21","country":"Poland","zipcode":"33-380"}]}]

db.collection.update({/** here filter the document that need to be updated*/},{$set:{"cards.$[x].CVV":"Something in the cards that need to be updated"}},{arrayFilters:[{"x.cardNumber":"46556456445564"}]})