diff --git a/core/modules/simpletest/tests/src/Unit/TestBaseTest.php b/core/modules/simpletest/tests/src/Unit/TestBaseTest.php
index 877d6e5..3baa1d7 100644
--- a/core/modules/simpletest/tests/src/Unit/TestBaseTest.php
+++ b/core/modules/simpletest/tests/src/Unit/TestBaseTest.php
@@ -5,6 +5,7 @@
 use Drupal\Tests\UnitTestCase;
 
 /**
+ * @requires extension curl
  * @coversDefaultClass \Drupal\simpletest\TestBase
  * @group simpletest
  */
diff --git a/core/modules/simpletest/tests/src/Unit/WebTestBaseTest.php b/core/modules/simpletest/tests/src/Unit/WebTestBaseTest.php
index 619ee74..1c087a6 100644
--- a/core/modules/simpletest/tests/src/Unit/WebTestBaseTest.php
+++ b/core/modules/simpletest/tests/src/Unit/WebTestBaseTest.php
@@ -5,6 +5,7 @@
 use Drupal\Tests\UnitTestCase;
 
 /**
+ * @requires extension curl
  * @coversDefaultClass \Drupal\simpletest\WebTestBase
  * @group simpletest
  */
diff --git a/core/tests/Drupal/Tests/Core/Image/ImageTest.php b/core/tests/Drupal/Tests/Core/Image/ImageTest.php
index 844dadb..312bbda 100644
--- a/core/tests/Drupal/Tests/Core/Image/ImageTest.php
+++ b/core/tests/Drupal/Tests/Core/Image/ImageTest.php
@@ -9,6 +9,7 @@
 /**
  * Tests the image class.
  *
+ * @requires extension gd
  * @group Image
  */
 class ImageTest extends UnitTestCase {