Is it permissible, in Sharia, to change one's family name to escape the stigma of belonging to a specific tribe in a tribal society, in order to protect one's children and free oneself from backward behaviors in that society?

The standard for Allah's guardianship and love for His servants is faith and piety. The noblest among people are the most pious. Boasting about lineage and disparaging ancestry are matters of the pre-Islamic era (Jahiliyyah). Love and loyalty are due to believers, regardless of their origins. No one has superiority over another except through piety. Affiliation with a tribe is for identification, not for boasting. Disparaging tribes and belittling their status is not permissible, just as it is not permissible for a person to disown their lineage or change their family name and affiliate with another, as this is among the gravest sins. The person concerned should be patient, fear Allah, and seek permissible solutions.