virtualbox-dkms 5.2.8-dfsg-5: virtualbox kernel module failed to build

Using Ubuntu 18.04 (updated 4 April 2018) on Dell XPS 13 Developer Edition - XPS 9360. Worked previously.

ProblemType: Package
DistroRelease: Ubuntu 18.04
Package: virtualbox-dkms 5.2.8-dfsg-5
ProcVersionSignature: Ubuntu 4.15.0-14.15-generic 4.15.15
Uname: Linux 4.15.0-14-generic x86_64
ApportVersion: 2.20.9-0ubuntu2
Architecture: amd64
DKMSKernelVersion: 4.15.0-14-generic
Date: Wed Apr 4 08:36:05 2018
InstallationDate: Installed on 2018-03-15 (19 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Alpha amd64 (20180315)
PackageArchitecture: all
PackageVersion: 5.2.8-dfsg-5
Python3Details: /usr/bin/python3.6, Python 3.6.5, python3-minimal, 3.6.5-2
PythonDetails: /usr/bin/python2.7, Python 2.7.14+, python-minimal, 2.7.14-4
RelatedPackageVersions:
 dpkg 1.19.0.5ubuntu1
 apt 1.6~beta1
SourcePackage: virtualbox
Title: virtualbox-dkms 5.2.8-dfsg-5: virtualbox kernel module failed to build
UpgradeStatus: No upgrade log present (probably fresh install)