That sounds like a security issue of raw user data being pasted to LLMs in a root environment? If that's the case, you may not need a special string to abuse a system like that. That's prompt injection.
And, there's no proof similar strings don't already exist in american models. What if "{id}_{url}" works to send it to an arbitrary URL, not a preset XYZ one?
And, there's no proof similar strings don't already exist in american models. What if "{id}_{url}" works to send it to an arbitrary URL, not a preset XYZ one?