- To exploit this across the internet or LAN, a miscreant needs to reach your CUPS service on UDP port 631. Hopefully none of you have that facing the public internet. The miscreant also has to wait for you to start a print job.
- If port 631 isn't directly reachable, an attacker may be able to spoof zeroconf, mDNS, or DNS-SD advertisements to achieve exploitation on a LAN. Details of that path will be disclosed later, we're promised.
So don't expose 631 to the internet (why would you?) and know who's on your network. Be careful printing things on an untrusted network.
It's serious, but seems like a wonky attack vector for most.