WASM can't magically make memory-unsafe languages memory-safe. You can still have memory leaks and buffer overflows, but (assuming a correct WASM implementation

WASM can't magically make memory-unsafe languages memory-safe. You can still have memory leaks and buffer overflows, but (assuming a correct WASM implementation) a buffer overflow can not result in memory access outside the WASM instance's memory space - unless you provide it with the facilities to do so.