As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FUMES ODOR IN CABIN AT START OF DESCENT. MAINTENANCE DETERMINED THE APU WAS THE SOURCE OF THE ODOR DUE TO OIL LEAKS. REPLACED APU PER JOB CARD 26L31049003. ACCOMPLISHED DECONTAMINATION OF ENVIRONMENTAL CONTROL SYSYEM AND SATISFACTORY OPERATIONAL CHECK.