diff --git a/tests/UtilsTest.php b/tests/UtilsTest.php
index c2e108a..1780922 100644
--- a/tests/UtilsTest.php
+++ b/tests/UtilsTest.php
@@ -12,7 +12,7 @@
 use Framework\Crypto\Utils;
 use PHPUnit\Framework\TestCase;
 
-class UtilsTest extends TestCase
+final class UtilsTest extends TestCase
 {
     public function testHexBin() : void
     {