I don't have the log, but I have read it and it causes a crash in my server.

I have [1.12.2] SecurityCraft v1.8.17.jar version installed, I will try to update it to v1.8.19.1

If you are still experiencing crashes after updating the mod to v1.8.19.1 or later, please reply with the crash report from the Password-protected Furnace crash. You can find that file in the crash-reports folder in the same place where the mods folder is located.