What is the stated reasoning for arbitrary code execution as a feature? Seems pretty mad to me.
- ESLint, the most commonly used linter in the JavaScript ecosystem uses a JavaScript file for configuration (eslint.config.mjs), so if you open a JS project and want your editor to show you warnings from the linter, an extension needs to run that JS
- In Elixir, project configuration is written in code (mix.exs), so if you open an Elixir project and want the language server to provide you with hints (errors, warnings and such), the language server needs to execute that code to get the project configuration. More generally it will probably want to expand macros in the project, which is also code execution.
- For many languages in general, in order to analyze code, editor extensions need to build the project, and this often results in code execution (like through macros or build scripts like build.rs, which I believe rust-analyzer executes)
(It can also be pointed out that a lot of these are granular under the hood. In addition to Restricted Mode as a generally available sandbox, you have all sorts of workspace level controls over tasks.json and the Extensions you have installed and active for that workspace. Not to mention a robust multi-profile system where you can narrow Extensions to specific roles and moods. But most of us tend to want to fall into habits of having a "kitchen sink" profile with everything always available and don't want to think about granular security controls.)
(I think some people are fixating on the specific feature that's mentioned in the article. The reason this pop-up exists is that there are many ways that this code execution could happen. Disabling this one feature doesn't make it safe, and this feature if not present, could still be achieved by abusing other capabilities that exist in the vs code ecosystem)
Bundling running those into the editor seems like the mad part to me, but I've missed the whole VSCode train so probably something I'm missing.
The easiest example is JS testing. Most test harnesses use a JS file for configuration. If you don't know how the harness is configured how do you know you are parsing the right tests?
Most test frameworks in JS use the define/it `define("some test colection", () => it("some test", () => /* …test code… */))` pattern. Tests are built as callbacks to functions.
In theory, sure, you could "just" try to RegEx out the `define("name"` and `it("name"` patterns, but it becomes harder to track nesting than you think it is with just RegEx. Then you realize that because those are code callbacks, no one is stopped from building meta-test suites with things like `for (thing of someTextMatrix) { it(`handles ${thing}`, () => /* …parametric test on thing… */ }`.
The test language used most in JS is JS. It's a lot harder problem than "just parsing" to figure out. In most cases a test harness needs to run the JS files to collect the full information about the test suite. Being JS files they are Turing Complete and open to doing whatever they want. Many times the test harnesses are running in a full Node environment with access to the entire filesystem and more.
Most of that applies to other test harnesses in other languages as well. To get the full suite of possible tests you need to be able to build that language and run it. How much of a sandbox that language has in that case shifts, but often it is still a sandbox with ways to escape. (We've proven that there's an escape Zero Day in the Universal Turing Machine, escapes are in some ways inevitable in any and all Turing Complete languages.)