Widebody; Low Wing; 2 Turbojet Eng
Maintenance Airframe; Maintenance Powerplant
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
General Maintenance Action
Procedure
Aircraft X has an open item. It states 'unknown substance throughout aircraft interior; ceiling panels; speaker cover; [and] cabin door area. Aircraft interior cleaning required...' It is my understanding that an unknown substance must be identified before we could fly the aircraft. [Company] is flying a plane in violation of the [Company Manual].
Mechanic reported a Widebody aircraft has an open item stating unknown substance throughout the passenger cabin surfaces.