diff --git a/tools/osbuilder/rootfs-builder/cbl-mariner/rootfs_lib.sh b/tools/osbuilder/rootfs-builder/cbl-mariner/rootfs_lib.sh
index f96142d7eb..eff847cc8d 100644
--- a/tools/osbuilder/rootfs-builder/cbl-mariner/rootfs_lib.sh
+++ b/tools/osbuilder/rootfs-builder/cbl-mariner/rootfs_lib.sh
@@ -9,7 +9,7 @@ build_rootfs()
 	# Mandatory
 	local ROOTFS_DIR="$1"
 
-	[ -z "$ROOTFS_DIR" ] && die "need rootfs"
+	[[ -z "${ROOTFS_DIR}" ]] && die "need rootfs"
 
 	# In case of support EXTRA packages, use it to allow
 	# users add more packages to the base rootfs
@@ -19,10 +19,12 @@ build_rootfs()
 	mkdir -p "${ROOTFS_DIR}"
 	PKG_MANAGER="tdnf"
 
+	# shellcheck disable=SC2154
 	DNF="${PKG_MANAGER} -y --installroot=${ROOTFS_DIR} --noplugins --releasever=${OS_VERSION}"
 
 	info "install packages for rootfs"
-	$DNF install ${EXTRA_PKGS} ${PACKAGES}
+	# shellcheck disable=SC2154,SC2086
+	${DNF} install ${EXTRA_PKGS} ${PACKAGES}
 
-	rm -rf ${ROOTFS_DIR}/usr/share/{bash-completion,cracklib,doc,info,locale,man,misc,pixmaps,terminfo,zoneinfo,zsh}
+	rm -rf "${ROOTFS_DIR}"/usr/share/{bash-completion,cracklib,doc,info,locale,man,misc,pixmaps,terminfo,zoneinfo,zsh}
 }