When zx is invoked with –prefer-local=, the CLI creates a symlink named ./node_modules pointing to /node_modules. Due to a logic error in src/cli.ts (linkNodeModules / cleanup), the function returns the target path instead of the alias (symlink path). The later cleanup routine removes what it received, which deletes the target directory itself. Result: zx can delete an external /node_modules outside the current working directory.
The product uses a name or reference to access a resource, but the name/reference resolves to a resource that is outside of the intended control sphere.