How to get inside a Samsung front-loading washer to track down a leak
Looking at the top/rear of the washer---you'll see two silver (about 12 mm ) screws---remove those using a phillips screwdriver.
Standing at the front of the washer---grasp the TOP COVER with both hands and firmly slide the TOP COVER rearward about 1-2 inches and lift off/remove the cover.
Start a short wash cycle (select the SILVER CARE option)
Using a bright flashlight---examine the internals of the washer during the cycle.
There are two possibles that come to mind...
1) Leaking hose that leads to the SILVER CARE MODULE (split/ruptured hose)
2) A puncture/hole in either the DRAIN HOSE or the soft/black BELLOWS HOSE next to the DRAIN MOTOR/PUMP ASSY---usually caused by a bra-wire or nail.
The back access panel can also be removed (4 screws) for a better view of the bottom of the washer and DRAIN MOTOR area.
Source: Samsung WF448AAPXAA washer Leaking water from bottom of machine