Information
System Integrity Protection is a security feature introduced in OS X 10.11 El Capitan. System Integrity Protection restricts access to System domain locations and restricts runtime attachment to system processes. Any attempt to attempt to inspect or attach to a system process will fail. Kernel Extensions are now restricted to /Library/Extensions and are required to be signed with a Developer ID.
Rationale:
Running without System Integrity Protection on a production system runs the risk of the modification of system binaries or code injection of system processes that would otherwise be protected by SIP.
Impact:
System binaries and processes could become compromised
Solution
Perform the following while booted in macOS Recovery Partition.
Select Terminal from the Utilities menu
Run the following command in Terminal:
/usr/bin/csrutil enable
The output should be:
Successfully enabled System Integrity Protection. Please restart the machine for the changes to take effect.
Reboot.
If a change is to the status is attempted from the booted Operating System rather than the recovery partition an error will be generated.
csrutil: failed to modify system integrity configuration. This tool needs to be executed from the Recovery OS.