As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: CORROSION AROUND AFT LAVATORY EXHAUST VENT. CORROSION OF FUSELAGE SKIN AROUND AFT LAVATORY EXHAUST VENT AT STA 1968 BETWEEN STR 35L AND STR 36L, MEASURING L=5.0 IN, W=2.5 IN, D=0.1 IN. ACCOMPLISHED PERMANENT REINFORCING DOUBLER REPAIR IAW B777 SRM 53-70-01-2R-1.