A 58-year-old man with advanced pancreatic cancer presents with acute onset of bleeding from multiple sites (gum bleeding, hematuria, melena). His wife reports he was well 2 days ago. Physical examination reveals petechiae, ecchymoses, and hepatomegaly. Laboratory results: Hemoglobin 7.8 g/dL, Platelet count 32,000/μL, PT 28 sec (control 12 sec), aPTT 58 sec (control 32 sec), Fibrinogen 0.8 g/L (normal 2–4 g/L), D-dimer 8.5 μg/mL (normal <0.5 μg/mL), Prothrombin time ratio (INR) 2.3. Peripheral blood smear shows schistocytes. What is the primary mechanism of coagulation abnormality in this patient?