diff --git a/puppet/zulip/files/nagios_plugins/zulip_app_frontend/check_worker_memory b/puppet/zulip/files/nagios_plugins/zulip_app_frontend/check_worker_memory
index b40634d01c..a3b863e80a 100755
--- a/puppet/zulip/files/nagios_plugins/zulip_app_frontend/check_worker_memory
+++ b/puppet/zulip/files/nagios_plugins/zulip_app_frontend/check_worker_memory
@@ -9,9 +9,10 @@ if [ -z "$processes" ]; then
     echo "No workers running"
     exit 0
 fi
-ps -o vsize,size,pid,user,command --sort -vsize $processes > "$datafile"
+mapfile -t processes <<< "$processes"
+ps -o vsize,size,pid,user,command --sort -vsize "${processes[@]}" > "$datafile"
 cat "$datafile"
-top_worker=$(cat "$datafile" | head -n2 | tail -n1)
+top_worker=$(head -n2 "$datafile" | tail -n1)
 top_worker_memory_usage=$(echo "$top_worker" | cut -f1 -d" ")
 rm -f "$datafile"
 if [ "$top_worker_memory_usage" -gt 800000 ]; then