Over at Google’s Project Zero blog, Natalie Silvanovich looks at
some of the bugs the project has found in WebAssembly
WebAssembly GC [garbage collection] is another potential feature of WebAssembly that could lead to security problems. Currently, some uses of WebAssembly have performance problems due to the lack of higher-level memory management in WebAssembly. For example, it is difficult to implement a performant Java Virtual Machine in WebAssembly. If WebAssembly GC is implemented, it will increase the number of applications that WebAssembly can be used for, but it will also make it more likely that vulnerabilities related to memory management will occur in both WebAssembly engines and applications written in WebAssembly.