diff --git a/src/crypto.c b/src/crypto.c
index 88de357d5d..99e9f08576 100644
--- a/src/crypto.c
+++ b/src/crypto.c
@@ -280,7 +280,7 @@ sign_bct(build_image_context *context,
 					bct) != 0)
 		return -ENODATA;
 
-	hash_buffer = malloc(hash_size);
+	hash_buffer = calloc(1, hash_size);
 	if (hash_buffer == NULL)
 		return -ENOMEM;
 	e = sign_data_block(bct + Offset, length, hash_buffer);
diff --git a/src/data_layout.c b/src/data_layout.c
index ae6212683d..cae4c37da5 100644
--- a/src/data_layout.c
+++ b/src/data_layout.c
@@ -391,7 +391,7 @@ write_bootloaders(build_image_context *context)
 	g_soc_config->get_value(token_bootloaders_max,
 			&bootloaders_max, context->bct);
 
-	hash_buffer = malloc(hash_size);
+	hash_buffer = calloc(1, hash_size);
 	if (hash_buffer == NULL)
 		return -ENOMEM;