Short answer
Prevention is wise, as durian isn't good for cats. Its high fat and sugar content can upset their stomach, and the strong smell often deters them anyway. To be safe, store durian in a sealed container inside a closed pantry or cupboard your cat cannot access. It's also helpful to train a solid 'leave it' command with high-value treats, so your cat learns to ignore dropped food. If your cat does manage to get a tiny taste, watch for vomiting or diarrhea and call your vet if those signs appear.
Durian — Food safety facts
Feed with care · Cats · full breakdown on the linked food page
Very high in fat and sugar, and the smell alone puts many pets off. Small amounts at most.
The full verdict, portion guidance and serving notes are collected on the Durian food facts page.