A very serious exploit for Apple systems running the High Sierra OS has come to light. You can read more about it here:
For a short-term fix Apple suggested this:
In working on a long-term fix, Apple created another issue in which file shares/sharing is broken. You can read more about that one here:
While a fix for that is pending, the manual steps to fix it are as follows:
1. Open the Terminal app, which is in the Utilities folder of your Applications folder.
2. Type sudo /usr/libexec/configureLocalKDC and press Return.
3. Enter your administrator password and press Return.
4. Quit the Terminal app.
If you need help with either of these issues or their subsequent patches/fixes, please give us a call at ESG!