The Huawei Modem Unlocker V577 software is designed with safety and security in mind:

The information provided in this article is for educational purposes only. The use of the Huawei Modem Unlocker V577 by Bojs 328 New software may void your warranty or violate your carrier's terms of service. Users are advised to proceed with caution and at their own risk.

released this lightweight tool to provide a free alternative to official unlock codes. Google Groups How it Worked