diff --git a/storage/storage.c b/storage/storage.c
index 59b0a8e4a..1d9713c7b 100644
--- a/storage/storage.c
+++ b/storage/storage.c
@@ -572,9 +572,9 @@ static void stretch_pin(const uint8_t *pin, size_t pin_len,
     ui_progress(PIN_PBKDF2_MS / 10);
   }
 #ifdef STM32U5
-  uint8_t stretched_pin_tmp[OPTIGA_PIN_SECRET_SIZE] = {0};
+  uint8_t stretched_pin_tmp[SHA256_DIGEST_LENGTH] = {0};
   pbkdf2_hmac_sha256_Final(&ctx, stretched_pin_tmp);
-  ensure(secure_aes_ecb_encrypt_hw(stretched_pin_tmp, OPTIGA_PIN_SECRET_SIZE,
+  ensure(secure_aes_ecb_encrypt_hw(stretched_pin_tmp, SHA256_DIGEST_LENGTH,
                                    stretched_pin, SECURE_AES_KEY_XORK),
          "secure_aes pin stretch failed");
   memzero(stretched_pin_tmp, sizeof(stretched_pin_tmp));