diff --git a/target/linux/ath79/image/generic-ubnt.mk b/target/linux/ath79/image/generic-ubnt.mk
index 8a45fb09d1..05847cc3a2 100644
--- a/target/linux/ath79/image/generic-ubnt.mk
+++ b/target/linux/ath79/image/generic-ubnt.mk
@@ -90,8 +90,7 @@ define Device/ubnt_acb-isp
   UBNT_BOARD := ACB-ISP
   UBNT_CHIP := qca9533
   UBNT_TYPE := ACB
-  UBNT_VERSION := 6.0.0
-  IMAGES := sysupgrade.bin
+  UBNT_VERSION := 2.5.0
 endef
 TARGET_DEVICES += ubnt_acb-isp
 
diff --git a/tools/firmware-utils/src/mkfwimage.c b/tools/firmware-utils/src/mkfwimage.c
index c8737386a2..c9d838a2e1 100644
--- a/tools/firmware-utils/src/mkfwimage.c
+++ b/tools/firmware-utils/src/mkfwimage.c
@@ -128,6 +128,15 @@ struct fw_info fw_info[] = {
 		},
 		.sign = true,
 	},
+	{
+		.name = "ACB-ISP",
+		.fw_layout = {
+			.kern_start	=	0x9f050000,
+			.kern_entry	=	0x80002000,
+			.firmware_max_length=	0x00F60000,
+		},
+		.sign = true,
+	},
 	{
 		.name = "",
 	},