System for protecting a mobile device against malware or harmful communications via calls and SMSs. A security module for a personal mobile device protects the device (and the user) against malicious communication, unauthorized access to resources and user private data, and against other security threats. The security module includes a combination of some or all of the following features: control of third-party applications, validation of the SMS sender's number, protection against fake contact name of the SMS sender, collection of data about fraudulent and spam SMS messages, robust sending of SOS SMSs and SOS e-mails with geographic coordinates of the mobile device, verification of validity of the base station, deletion of user data from a mobile device remotely, locking of a phone until the password is entered and filtering calls and SMS messages.