Babel vulnerable to arbitrary code execution when compiling specifically crafted malicious code
### Impact
Using Babel to compile code that was specifically crafted by an attacker can lead to arbitrary code execution during compilation, when using plugins that rely on the `path.evaluate()`or `path.evaluateTruthy()` internal Babel methods.
Known affected plugins are:
- `@babel/plugin-transform-runtime`
- `@babel/preset-env` when using its `useBuiltIns`
https://babeljs.io/docs/babel-preset-env#usebuiltins option
- Any "polyfill provider" plugin that depends on `@babel/helper-define-polyfill-provider`, such as `babel-plugin-polyfill-corejs3`, `babel-plugin-polyfill-corejs2`, `babel-plugin-polyfill-es-shims`, `babel-plugin-polyfill-regenerator`
No other plugins under the `@babel/` namespace are impacted, but third-party plugins might be.
**Users that only compile trusted code are not impacted.**
### Patches
The vulnerability has been fixed in `@babel/traverse@7.23.2`.
Babel 6 does not receive security fixes anymore (see Babel's security policy
https://github.com/babel/babel/security/policy) hence there is no patch planned for `babel-traverse@6`.
### Workarounds
- Upgrade `@babel/traverse` to v7.23.2 or higher. You can do this by deleting it from your package manager's lockfile and re-installing the dependencies. `@babel/core` >=7.23.2 will automatically pull in a non-vulnerable version.
- If you cannot upgrade `@babel/traverse` and are using one of the affected packages mentioned above, upgrade them to their latest version to avoid triggering the vulnerable code path in affected `@babel/traverse` versions:
- `@babel/plugin-transform-runtime` v7.23.2
- `@babel/preset-env` v7.23.2
- `@babel/helper-define-polyfill-provider` v0.4.3
- `babel-plugin-polyfill-corejs2` v0.4.6
- `babel-plugin-polyfill-corejs3` v0.8.5
- `babel-plugin-polyfill-es-shims` v0.10.0
- `babel-plugin-polyfill-regenerator` v0.5.3