diff -u b/core/modules/update/src/UpdateManager.php b/core/modules/update/src/UpdateManager.php
--- b/core/modules/update/src/UpdateManager.php
+++ b/core/modules/update/src/UpdateManager.php
@@ -246,8 +246,7 @@
       'items' => [
         '#theme' => 'item_list',
         '#items' => [
-          // @todo Need a real link for this.
-          'documentation_link' => $this->t('See <a href="@url">the Drupal.org handbook</a> for possible reasons this could happen and what you can do to resolve them.', ['@url' => 'https://drupal.org/todo']),
+          'documentation_link' => $this->t('See <a href="@url">PHP OpenSSL requirements</a> in the Drupal.org handbook for possible reasons this could happen and what you can do to resolve them.', ['@url' => 'https://www.drupal.org/node/3170647']),
         ],
       ],
     ];