According to Selmie's Notes found inside the cabin, the legendary Shield Surfer Selmie set up the lodge for shield surfers, treasure hunters, and anyone else visiting the mountains and left behind a notebook containing information on how to survive on the mountain. The cabin also contains a Bed, a Cooking Pot, Flint, Barrels containing provisions, and a Treasure Chest containing a Meteor Rod. It is one of two cabins owned by Selmie the other being her personal cabin at Selmie's Spot.
Even inside the cabin, it is still cold enough that Link must have Level 2 Cold Resistance (via Cold Resistant Armor and/or eating "Spicy" food). Link can also stand next to the cooking pot or create Campfires in areas of the cabin that the heat of the cooking pot does not reach.
However Link must be careful of the traveler camped outside near the cabin as he is actually a disguised Yiga Footsoldier. However like all disguised Yiga, Link can avoid fighting them by ignoring and not speaking to them.