If there is a vulnerability in a system you control, you can mitigate it until it can be patched, or if necessary disable access to it until it can be patched.

If there is a vulnerability in a system you control, you can mitigate it until it can be patched, or if necessary disable access to it until it can be patched. If there is a vulnerability in a system controlled by an untrusted party that already has your sensitive data on it, you're pwned.