diff --git a/fs/ubi/Config.in b/fs/ubi/Config.in
index 85b1c56bb0..3427ea0518 100644
--- a/fs/ubi/Config.in
+++ b/fs/ubi/Config.in
@@ -38,6 +38,11 @@ config BR2_TARGET_ROOTFS_UBI_USE_CUSTOM_CONFIG
 	  So the volume defined for the root filesystem can specify the
 	  image path as:  image=BR2_ROOTFS_UBIFS_PATH
 
+	  Buildroot also replaces the string "BINARIES_DIR" with the
+	  value of $(BINARIES_DIR), so that it is possible to reference
+	  other build artefacts (e.g. to include the kernel in a UBI
+	  volume).
+
 config BR2_TARGET_ROOTFS_UBI_CUSTOM_CONFIG_FILE
 	string "Configuration file path"
 	depends on BR2_TARGET_ROOTFS_UBI_USE_CUSTOM_CONFIG
diff --git a/fs/ubi/ubi.mk b/fs/ubi/ubi.mk
index d848f8b23a..54bb81ea08 100644
--- a/fs/ubi/ubi.mk
+++ b/fs/ubi/ubi.mk
@@ -23,7 +23,7 @@ endif
 # don't use sed -i as it misbehaves on systems with SELinux enabled when this is
 # executed through fakeroot (see #9386)
 define ROOTFS_UBI_CMD
-	sed 's;BR2_ROOTFS_UBIFS_PATH;$@fs;' \
+	sed 's;BR2_ROOTFS_UBIFS_PATH;$@fs;;s;BINARIES_DIR;$(BINARIES_DIR);' \
 		$(UBI_UBINIZE_CONFIG_FILE_PATH) > $(BUILD_DIR)/ubinize.cfg
 	$(HOST_DIR)/sbin/ubinize -o $@ $(UBI_UBINIZE_OPTS) $(BUILD_DIR)/ubinize.cfg
 	rm $(BUILD_DIR)/ubinize.cfg