diff --git a/target/imagebuilder/files/Makefile b/target/imagebuilder/files/Makefile
index e502ffc4b2..c7ee3e1e21 100644
--- a/target/imagebuilder/files/Makefile
+++ b/target/imagebuilder/files/Makefile
@@ -260,6 +260,7 @@ else
 	)
 endif
 	$(call prepare_rootfs,$(TARGET_DIR),$(USER_FILES),$(DISABLED_SERVICES))
+	$(ESED) "s/(DISTRIB_DESCRIPTION='.+)'\$$/\\1 unofficial'/" $(TARGET_DIR)/etc/openwrt_release
 
 build_image: FORCE
 	@echo