diff --git a/tools/unit-tests/unit-image.c b/tools/unit-tests/unit-image.c
index 81f5b2d0..9a16f477 100644
--- a/tools/unit-tests/unit-image.c
+++ b/tools/unit-tests/unit-image.c
@@ -76,6 +76,13 @@ static const unsigned char pubkey_digest[SHA256_DIGEST_SIZE] = {
 };
 
 
+uint32_t wolfBoot_get_blob_version(uint8_t *blob)
+{
+    (void)blob;
+    return 1;
+}
+
+
 static unsigned char test_img_v200000000_signed_bin[] = {
       0x57, 0x4f, 0x4c, 0x46, 0x13, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
   0x00, 0xc2, 0xeb, 0x0b, 0xff, 0xff, 0xff, 0xff, 0x02, 0x00, 0x08, 0x00,