you must sign the kernel modules before using VirtualBox: vboxdrv vboxnetflt vboxnetadp code example
Example 1: how to sign virtualbox kernel modules
sudo -i
cd /root/module-signing
chmod 700 /root/module-signing/sign-vbox-modules
./sign-vbox-modules
Example 2: how to sign virtualbox kernel modules
sudo chmod 700 /root/bin/sign-vbox-modules
sudo -i sign-vbox-modules