A request is received to access a user account. A geolocation of a mobile device registered with the user account is obtained directly from the mobile device. Authentication credentials for the user account are verified for correctness. A mobile device geolocation verification request is transmitted to a cellular data provider. The cellular data provider is equipped to independently determine a true geolocation region of the mobile device for comparison with the geolocation of the mobile device as obtained directly from the mobile device. A verification response to the mobile device geolocation verification request is received from the cellular data provider. The verification response indicates whether or not the geolocation of the mobile device as obtained directly from the mobile device corresponds to the true geolocation region of the mobile device. A response to the access request based on the verification response is transmitted.