diff --git a/target/linux/ar71xx/base-files/lib/ar71xx.sh b/target/linux/ar71xx/base-files/lib/ar71xx.sh
index e0b8830161..0b18d0ce10 100755
--- a/target/linux/ar71xx/base-files/lib/ar71xx.sh
+++ b/target/linux/ar71xx/base-files/lib/ar71xx.sh
@@ -53,6 +53,15 @@ wndr3700_board_detect() {
 	AR71XX_MODEL="$machine"
 }
 
+cybertan_get_hw_magic() {
+	local part
+
+	part=$(find_mtd_part firmware)
+	[ -z "$part" ] && return 1
+
+	dd bs=8 count=1 skip=0 if=$part 2>/dev/null | hexdump -v -n 8 -e '1/1 "%02x"'
+}
+
 tplink_get_hwid() {
 	local part
 
diff --git a/target/linux/ar71xx/base-files/lib/upgrade/platform.sh b/target/linux/ar71xx/base-files/lib/upgrade/platform.sh
index 839ba4e77b..9d42404ac2 100755
--- a/target/linux/ar71xx/base-files/lib/upgrade/platform.sh
+++ b/target/linux/ar71xx/base-files/lib/upgrade/platform.sh
@@ -73,6 +73,22 @@ seama_get_type_magic() {
 	get_image "$@" | dd bs=1 count=4 skip=53 2>/dev/null | hexdump -v -n 4 -e '1/1 "%02x"'
 }
 
+cybertan_get_image_magic() {
+	get_image "$@" | dd bs=8 count=1 skip=0  2>/dev/null | hexdump -v -n 8 -e '1/1 "%02x"'
+}
+
+cybertan_check_image() {
+	local magic="$(cybertan_get_image_magic "$1")"
+	local fw_magic="$(cybertan_get_hw_magic)"
+
+	[ "$fw_magic" != "$magic" ] && {
+		echo "Invalid image, ID mismatch, got:$magic, but need:$fw_magic"
+		return 1
+	}
+
+	return 0
+}
+
 platform_check_image() {
 	local board=$(ar71xx_board_name)
 	local magic="$(get_magic_word "$1")"
@@ -155,6 +171,11 @@ platform_check_image() {
 		dir825b_check_image "$1" && return 0
 		;;
 
+	mynet-rext)
+		cybertan_check_image "$1" && return 0
+		return 1
+		;;
+
 	mynet-n600)
 		[ "$magic_long" != "5ea3a417" ] && {
 			echo "Invalid image, bad magic: $magic_long"