WASM Compared With Flash And Plugins

Flash, Shockwave, and NPAPI plugins were separate runtime/plugin stacks with broad native integration and a long history of high-impact security failures. WebAssembly is browser-native and runs under the web platform security model.

• WASM modules are validated before execution.
• They run in the same-origin, permissions, process isolation, and sandboxing model of modern browsers.
• They do not get automatic filesystem, device, DOM, or network authority.
• Host capabilities must be explicitly imported.