Comment 0 for bug 1719630

in its postinst script unattended-upgrade uses dpkg-vendor from dpkg-dev but does not depends on dpkg-dev which results in the following error:

# apt-get update && apt-get upgrade

Installing the packages goes well, except for, getting this warning.

Setting up unattended-upgrades (0.97ubuntu1) ...
/var/lib/dpkg/info/unattended-upgrades.postinst: 65:
/var/lib/dpkg/info/unattended-upgrades.postinst: dpkg-vendor: not found
/var/lib/dpkg/info/unattended-upgrades.postinst: 66:
/var/lib/dpkg/info/unattended-upgrades.postinst: dpkg-vendor: not found
/var/lib/dpkg/info/unattended-upgrades.postinst: 124:
/var/lib/dpkg/info/unattended-upgrades.postinst: dpkg-vendor: not found
/var/lib/dpkg/info/unattended-upgrades.postinst: 125:
/var/lib/dpkg/info/unattended-upgrades.postinst: dpkg-vendor: not found

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: unattended-upgrades 0.97ubuntu1
ProcVersionSignature: Ubuntu 4.13.0-11.12-generic 4.13.1
Uname: Linux 4.13.0-11-generic x86_64
ApportVersion: 2.20.7-0ubuntu1
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Tue Sep 26 10:01:05 2017
InstallationDate: Installed on 2013-09-03 (1483 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Alpha amd64 (20130902)
PackageArchitecture: all
ProcEnviron:
 TERM=screen-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SourcePackage: unattended-upgrades
UpgradeStatus: No upgrade log present (probably fresh install)
modified.conffile..etc.apt.apt.conf.d.50unattended-upgrades: [modified]
mtime.conffile..etc.apt.apt.conf.d.50unattended-upgrades: 2017-09-05T01:34:04.573213