diff --git a/tools/cert_create/src/main.c b/tools/cert_create/src/main.c
index 2ba1101..1489cb0 100644
--- a/tools/cert_create/src/main.c
+++ b/tools/cert_create/src/main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -492,7 +492,12 @@
 			 */
 			switch (ext->type) {
 			case EXT_TYPE_NVCOUNTER:
-				if (ext->arg) {
+				if (ext->optional && ext->arg == NULL) {
+					/* Skip this NVCounter */
+					continue;
+				} else {
+					/* Checked by `check_cmd_params` */
+					assert(ext->arg != NULL);
 					nvctr = atoi(ext->arg);
 					CHECK_NULL(cert_ext, ext_new_nvcounter(ext_nid,
 						EXT_CRIT, nvctr));
@@ -505,7 +510,7 @@
 						memset(md, 0x0, SHA512_DIGEST_LENGTH);
 					} else {
 						/* Do not include this hash in the certificate */
-						break;
+						continue;
 					}
 				} else {
 					/* Calculate the hash of the file */