Symantec Endpoint Protection (SEP) for Mac detects /mach_kernel as a vulnerability and displays this notification.
Please note that this is an issue SEP and not an actual threat to your computer. The mach_kernel is legitimate.
To stop receiving this false vulnerability alert, you need to disable the notifications for this.
C:\Users\johnpaul.benedetti\Downloads\Archive\Screen Shot 2016-07-27 at 9.43.51 AM.png