Bring a large pot of lightly salted water to a boil. Cook spaghetti in the boiling water, stirring occasionally, until tender yet firm to the bite, about 12 minutes.
While spaghetti is cooking, melt butter in a large skillet over medium heat. Cook and stir leek until soft, about 5 minutes. Pour in white wine and simmer until almost all the wine has evaporated, 3 to 5 minutes. Stir in sour cream and 1 ladleful of spaghetti cooking water and mix well. Reduce heat to low. Add salmon and cook until it is cooked through, about 5 minutes. Season with salt and pepper. Stir in savory and thyme.
Drain spaghetti and toss with the creamy salmon. Serve sprinkled with Parmesan cheese.