Mozilla has equipped Firefox with new sandbox technology. The new sandbox technology should prevent a leak in Firefox, which could result in full access to the underlying operating system.
The sandbox technology is called RLBox. RLBox ensures that vulnerable third-party libraries are isolated.
Libraries are frequently used by Firefox, among other things, to decode media in the browser. Deian Stefan of the University of California San Diego reports that the university is involved in the development of RLBox.
The technology ensures that libraries and other parts of Firefox run in a WebAssembly (wasm) sandbox. For this purpose, the C++ and C code are converted to wasm code. The wasm code can then be converted to native code.
According to Mozilla, RLBox is a lightweight technique and easy to use. The browser developer, therefore, expects to place more parts of Firefox in this way in a sandbox in the coming months.
RLBox will be available in Firefox 74 for Linux, and Firefox 75 for Mac. The Windows version will be released later.
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