diff --git a/libpldm/firmware_update.c b/libpldm/firmware_update.c
index d3008b1..acb95fd 100644
--- a/libpldm/firmware_update.c
+++ b/libpldm/firmware_update.c
@@ -10,6 +10,7 @@
 {
 	switch (string_type) {
 	case PLDM_STR_TYPE_UNKNOWN:
+		return false;
 	case PLDM_STR_TYPE_ASCII:
 	case PLDM_STR_TYPE_UTF_8:
 	case PLDM_STR_TYPE_UTF_16: