Bring a large pot of water to a boil and cook pasta according to package directions. Drain.
While pasta is cooking, heat olive oil in a pan over medium heat. Cook onion just until softened, about 3 minutes. Stir in the curry powder and garam masala. Stir in the pumpkin. Slowly pour in the chicken broth and heavy cream. Reduce heat to a simmer and cook until thickened slightly, 3 – 5 minutes.
Add pasta to the sauce and toss to coat. Stir in salt. Add more if desired.
Transfer pasta to a serving dish, sprinkle with green onions and serve.