diff -Nru livecd-rootfs-2.578.5/debian/changelog livecd-rootfs-2.578.6/debian/changelog
--- livecd-rootfs-2.578.5/debian/changelog	2019-05-30 21:13:55.000000000 +0200
+++ livecd-rootfs-2.578.6/debian/changelog	2019-07-16 11:43:44.000000000 +0200
@@ -1,3 +1,13 @@
+livecd-rootfs (2.578.6) disco; urgency=medium
+
+  * Backport error-checking on determining snap bases.  LP: #1828500.
+
+  [ Tobias Koch ]
+  * Do proper error checking when calling snap-tool info to determine
+    the base of a snap.
+
+ -- Tobias Koch <tobias.koch@canonical.com>  Tue, 16 Jul 2019 11:43:44 +0200
+
 livecd-rootfs (2.578.5) disco; urgency=medium
 
   [ Balint Reczey ]
diff -Nru livecd-rootfs-2.578.5/live-build/functions livecd-rootfs-2.578.6/live-build/functions
--- livecd-rootfs-2.578.5/live-build/functions	2019-05-30 21:13:55.000000000 +0200
+++ livecd-rootfs-2.578.6/live-build/functions	2019-07-16 11:43:24.000000000 +0200
@@ -483,12 +483,20 @@
             ;;
         *)
             # Determine if and what core snap is needed
-            local core_snap=$(/usr/share/livecd-rootfs/snap-tool info \
+            local snap_info
+
+            snap_info=$(/usr/share/livecd-rootfs/snap-tool info \
                 --cohort-key="${COHORT_KEY:-}" \
-                --channel="$CHANNEL" "$SNAP_NAME" | \
-                grep '^base:' | awk '{print $2}'
+                --channel="$CHANNEL" "${SNAP_NAME}" \
             )
 
+            if [ $? -ne 0 ]; then
+                echo "Failed to retrieve base of $SNAP_NAME!"
+                exit 1
+            fi
+
+            local core_snap=$(echo "$snap_info" | grep '^base:' | awk '{print $2}')
+
             # If $core_snap is not the empty string then SNAP itself is not a core
             # snap and we must additionally seed the core snap.
             if [ -n "$core_snap" ]; then