diff --git a/core/Makefile b/core/Makefile
index e7d0e4c..9eae820 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1218,6 +1218,7 @@
 ifeq ($(BOARD_AVB_ENABLE),true)
 $(INSTALLED_BOOTIMAGE_TARGET): $(INTERNAL_PREBUILT_BOOTIMAGE) $(AVBTOOL) $(BOARD_AVB_BOOT_KEY_PATH)
 	cp $(INTERNAL_PREBUILT_BOOTIMAGE) $@
+	chmod +w $@
 	$(AVBTOOL) add_hash_footer \
 	    --image $@ \
 	    $(call get-partition-size-argument,$(BOARD_BOOTIMAGE_PARTITION_SIZE)) \
@@ -1286,6 +1287,7 @@
 ifeq ($(BOARD_AVB_ENABLE),true)
 $(INSTALLED_INIT_BOOT_IMAGE_TARGET): $(INTERNAL_PREBUILT_INIT_BOOT_IMAGE) $(AVBTOOL) $(BOARD_AVB_INIT_BOOT_KEY_PATH)
 	cp $(INTERNAL_PREBUILT_INIT_BOOT_IMAGE) $@
+	chmod +w $@
 	$(AVBTOOL) add_hash_footer \
 	    --image $@ \
 	    $(call get-partition-size-argument,$(BOARD_INIT_BOOT_IMAGE_PARTITION_SIZE)) \
@@ -3982,6 +3984,7 @@
 ifeq ($(BOARD_AVB_ENABLE),true)
 $(INSTALLED_DTBOIMAGE_TARGET): $(BOARD_PREBUILT_DTBOIMAGE) $(AVBTOOL) $(BOARD_AVB_DTBO_KEY_PATH)
 	cp $(BOARD_PREBUILT_DTBOIMAGE) $@
+	chmod +w $@
 	$(AVBTOOL) add_hash_footer \
 	    --image $@ \
 	    $(call get-partition-size-argument,$(BOARD_DTBOIMG_PARTITION_SIZE)) \