As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLT 433 - EN ROUTE DFW-MEX AT 7000 FEET, FLIGHT ATTENDANT NOTIFIED COCKPIT OF SMOKE IN CABIN. RETURNED DFW AND LANDED WITHOUT FURTHER INCIDENT. REPLACED APU AND ACCOMPLISHED PACK BURNOUT PER THE MM. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)