diff --git a/vm/openwrt.sh b/vm/openwrt.sh
index 60192ae7e..ea0474e58 100644
--- a/vm/openwrt.sh
+++ b/vm/openwrt.sh
@@ -315,7 +315,7 @@ function advanced_settings() {
     exit-script
   fi
 
-  if LAN_NETMASK=$(whiptail --backtitle "Proxmox VE Helper Scripts" --inputbox "Set a router netmmask" 8 58 $LAN_NETMASK --title "LAN NETMASK" --cancel-button Exit-Script 3>&1 1>&2 2>&3); then
+  if LAN_NETMASK=$(whiptail --backtitle "Proxmox VE Helper Scripts" --inputbox "Set a router netmask" 8 58 $LAN_NETMASK --title "LAN NETMASK" --cancel-button Exit-Script 3>&1 1>&2 2>&3); then
     if [ -z $LAN_NETMASK ]; then
       LAN_NETMASK="255.255.255.0"
     fi