diff -Nru sddm-0.14.0/debian/changelog sddm-0.14.0/debian/changelog
--- sddm-0.14.0/debian/changelog	2017-05-02 17:55:40.000000000 +0000
+++ sddm-0.14.0/debian/changelog	2018-02-11 00:25:09.000000000 +0000
@@ -1,3 +1,9 @@
+sddm (0.14.0-4ubuntu2) bionic; urgency=high
+
+  * Don't use an absolute path when setting $DESKTOP_SESSION (LP: #1668722).
+
+ -- Simon Quigley <tsimonq2@ubuntu.com>  Sat, 10 Feb 2018 18:25:09 -0600
+
 sddm (0.14.0-4ubuntu1) artful; urgency=medium
 
   [ Simon Quigley ]
diff -Nru sddm-0.14.0/debian/patches/fix-desktop-session-env-var.patch sddm-0.14.0/debian/patches/fix-desktop-session-env-var.patch
--- sddm-0.14.0/debian/patches/fix-desktop-session-env-var.patch	1970-01-01 00:00:00.000000000 +0000
+++ sddm-0.14.0/debian/patches/fix-desktop-session-env-var.patch	2018-02-10 03:32:47.000000000 +0000
@@ -0,0 +1,30 @@
+Description: DESKTOP_SESSION should only be the base name
+ When xorg takes DESKTOP_SESSION from SDDM and uses it to set XDG_DATA_DIRS,
+ the absolute path causes XDG_DATA_DIRS to contain paths which don't exist.
+ This makes packages (like Lubuntu's default settings) break when they need to
+ pull from /etc/xdg/xdg-$DESKTOP_SESSION.
+Author: Simon Quigley <tsimonq2@ubuntu.com>
+Bug: https://github.com/sddm/sddm/issues/852
+Bug-Ubuntu: https://bugs.launchpad.net/bugs/1668722
+Forwarded: yes
+Last-Update: 2018-02-09
+--- a/src/common/Session.cpp
++++ b/src/common/Session.cpp
+@@ -106,7 +106,7 @@ namespace SDDM {
+ 
+     void Session::setTo(Type type, const QString &_fileName)
+     {
+-        QString fileName(_fileName);
++        QString fileName = _fileName;
+         if (!fileName.endsWith(s_entryExtention))
+             fileName += s_entryExtention;
+ 
+@@ -160,6 +160,8 @@ namespace SDDM {
+ 
+         file.close();
+ 
++        m_fileName = fileName;
++
+         m_type = type;
+         m_valid = true;
+     }
diff -Nru sddm-0.14.0/debian/patches/series sddm-0.14.0/debian/patches/series
--- sddm-0.14.0/debian/patches/series	2017-05-02 17:55:40.000000000 +0000
+++ sddm-0.14.0/debian/patches/series	2018-02-09 23:22:33.000000000 +0000
@@ -9,3 +9,4 @@
 
 kubuntu_minimum_vt.diff
 kubuntu_nvidia-prime.diff
+fix-desktop-session-env-var.patch