The client's automatic updater now runs entirely on Jade Dynasty Mortal infrastructure.
The more important half of this change is the signing key. The client verifies a cryptographic signature on every patch list before applying anything, and it refuses to continue if that check fails. However, the key it shipped with is a widely circulated one, shared across many servers built from the same client - which means anyone holding the matching private key could have published an update your client would have accepted.
That key has been replaced with one generated for this server, and the private half never touches an internet-facing machine. Patches are signed by hand as part of preparing a release.
Practically: if someone were to take control of our patch server tomorrow, the worst they could do is stop updates from working. They could not push code to your computer.
The patch files are also served from a location the website cannot write to, so a website compromise cannot poison the update channel either.