This has shown up again in 18.04.
dpkg: warning: version '/etc/lsb-release' has bad syntax: version number does not start with digit
$ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=18.04 DISTRIB_CODENAME=bionic DISTRIB_DESCRIPTION="Ubuntu 18.04.3 LTS"
This has shown up again in 18.04.
dpkg: warning: version '/etc/lsb-release' has bad syntax: version number does not start with digit
$ cat /etc/lsb-release RELEASE= 18.04 CODENAME= bionic DESCRIPTION= "Ubuntu 18.04.3 LTS"
DISTRIB_ID=Ubuntu
DISTRIB_
DISTRIB_
DISTRIB_