diff --git a/sc_core/src/private_state.rs b/sc_core/src/private_state.rs
index f5b683a3..8641ab28 100644
--- a/sc_core/src/private_state.rs
+++ b/sc_core/src/private_state.rs
@@ -231,4 +231,11 @@ mod tests {
         assert_eq!(blob_from_vec.0[3..], [0u8; PRIVATE_BLOB_SIZE - 3]);
     }
 
+    #[test]
+    #[should_panic]
+    fn test_blob_from_fit_vec_panic() {
+        let data = vec![1u8; PRIVATE_BLOB_SIZE + 1];
+        let _ = produce_blob_from_fit_vec(data);
+    }
+
 }