C501 Captain reported a loss of cabin pressure and cabin door seal failure when water in door pressurization bleed lines froze necessitating a rapid descent from cruise altitude.

Narrative

My crew and I repositioned our airplane to ZZZ1 to execute a routine flight which was scheduled to depart from ZZZ1 to ZZZ2 at XA15. The flight leg to ZZZ1 was uneventful and normal. We performed our regular preflight inspections and received our IFR clearance and fuel load for the flight while our passengers showed at XA30. After providing a thorough safety briefing; I secured the cabin doors and we departed at XB01. The takeoff and climb were normal and we reached our cruise altitude of 36000 ft. At Approximately XB47; while in cruise we heard a sudden pop sound in cabin and an immediate rise in cabin altitude. The corrective action required of us to perform was to execute a [priority] descent to a safe altitude to where everyone can breathe normally without the need of a pressurized cabin as per our safety training. Hence; we donned our masks; ran our checklists; notified ATC and Passengers and executed a [priority] descent in less than 3 minutes down to 10;000 ft. No injuries were reported on board and I as PIC (pilot in command) made an executive decision to divert to ZZZ which was a familiar airport and within 20 miles from where we were. The flight was intended for a specific mission however as PIC; safety of my crew and passengers at the time was my primary concern.Later on the ground we realized water in the bleed lines pressurizing the door seal was the culprit and it had iced up at high altitudes causing this occurrence. Maintenance was able to clear up water and also implemented regular safety checks to ensure that this doesn't happen ever again.