kdesudo crashes when starting partitionmanager on Kubuntu 16.04.3 LTS

Steps to reproduce:
1. Get a clean installation of Kubuntu 16.04.3 LTS amd64
2. Install
3. In the K Menu go to "Programs" -> "System" -> "Partition editor"
4. Click on the entry
5. kdesudo opens up
6. Enter your password

Expected behaviour:
If password is correct the application /usr/bin/partitionmanager gets launched.

Observed behaviour:
kdesudo dialog freezes until manual termination.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: kdesudo 3.4.2.4+repack-2ubuntu4
ProcVersionSignature: Ubuntu 4.10.0-42.46~16.04.1-generic 4.10.17
Uname: Linux 4.10.0-42-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.14
Architecture: amd64
Date: Sun Dec 10 13:38:16 2017
InstallationDate: Installed on 2017-12-09 (0 days ago)
InstallationMedia: Kubuntu 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
ProcEnviron:
 LANGUAGE=
 TERM=xterm
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: kdesudo
UpgradeStatus: No upgrade log present (probably fresh install)