alt Hacker NewsIsn't this the industry expectation in that kind of equipment? If it was signed by a real CA the cert. could expire and render the equipment unable to communicate.
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stephbook • yesterday at 1:02 PM
also you can't pin the user/pw to the machine with a note, because someone might need remote access. better stick with admin/admin
That’s a tough question. If your PLC is on an airgapped LAN, admin/admin is not great security hygiene but you’ve reduced most of the risk by airgapping.
On my project the service I wrote was doing bidirectional communication with the PLC over OPCUA. The server running this pod was connected to the internet, so it was critical to have proper TLS for the OPCUA client/server. Rotating LetsEncrypt certs on the system every 45 days is a lot of toil, but using a self-signed cert that expires in 2040 from some dev laptop doesn’t pass muster in most organizations either.
That’s just the OPCUA path.. In these projects You also typically see WinCC HMIs that can talk to the PLC from anywhere on the network without TLS. And also SIMATIC Web Server pages - minimally secured by default, and the amount of info you can grok about the system in Chrome Dev Tools is troubling.