As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED. IN FLIGHT AT 34,000 ECAM WITH MASTER CAUTION, SMOKE LAVATORY SMOKE. FLIGHT ATTENDANTS CHECKED FORWARD LAVATORY AND FOUND NO SMOKE OR FUMES. TROUBLESHOT IAW TSM 26-17-00. FOUND FORWARD LAVATORY AIR EXTRACT FILTER CLOGGED. REPLACED FILTER IAW AMM 21-23-00.