I don't have a definitive source readily available, but from talking to people who were investigating the technical aspects, connection between the printer and slicer software will be mutually authenticated using a certificate that will issued by Bambu Cloud, issued only to blessed 1st party software, and verified by the printer upon connection over the local network.
So your blessed Bambu Studio instance connects to Bambu Cloud and requests a certificate, the server issues the certificate to you (or not), and then Bambu Studio may use it to connect to the printer on your LAN.
The certificates have an expiration time of 1 year, meaning that the printer functionality would severely degraded (missing network connectivity), at most 1 year after they take the servers offline or stop issuing certificates for any reason.
1) That cert is on the /client/ side, not in the printer. It has nothing to do with printer functionality, only with talking to the printer.
2) Expired certs do not mean things automatically get rejected. Using and allowing expired or self-signed certs is routine in the IoT world where certs on devices can't readily be updated. But again, that cert isn't from the printer.
3) Expired certs, just like the self-signed certs that are so commonly used, still result in things being encrypted on the wire. And often that's the point.
It seems to me that someone found/exported the cert, and is trying to make all sorts of WHAT-IF or THIS-COULD-MEAN-THE-WORST claims but are lacking some significant understanding. Without understanding the architecture and the rest of the code, and perhaps seeing that cert be used, this is just an artifact found in the distributed beta application.
I mean that the extracted cert that's going around is from the client (Bambu Connect) side. Everything it would get used for is a function of the client and how it talks /to/ the printer.
Even if it is used to sign some communications, it doesn't matter if it's expired or not on the server side (the printer side), unless the server chooses not to accept it. And then updating it would be a matter of updating Connect; the client.
There's no reason -- other than hyperbole -- to infer that a certificate which expires on the client side will cause the printer to stop doing anything.
For a web-y example, think of how a website which needs a client cert for auth -- like lots of gov't stuff -- would handle a client cert expiring. It'd either accept it anyway, or reject it. But it wouldn't mean the website breaks. And thus claims of that client certificate's expiration being a killswitch for printers is simply wrong.
So your blessed Bambu Studio instance connects to Bambu Cloud and requests a certificate, the server issues the certificate to you (or not), and then Bambu Studio may use it to connect to the printer on your LAN.
The certificates have an expiration time of 1 year, meaning that the printer functionality would severely degraded (missing network connectivity), at most 1 year after they take the servers offline or stop issuing certificates for any reason.
Not a definitive source for what I said, but it contains some information: https://hackaday.com/2025/01/19/bambu-connects-authenticatio...