diff --git a/core/modules/views/src/Plugin/views/row/RssFields.php b/core/modules/views/src/Plugin/views/row/RssFields.php
index 9a31a028f0..2960647b03 100644
--- a/core/modules/views/src/Plugin/views/row/RssFields.php
+++ b/core/modules/views/src/Plugin/views/row/RssFields.php
@@ -139,9 +139,7 @@ public function render($row) {
     // Create the RSS item object.
     $item = new \stdClass();
     $item->title = $this->getField($row_index, $this->options['title_field']);
-    // @todo Views should expect and store a leading /. See:
-    //   https://www.drupal.org/node/2423913
-    $item->link = Url::fromUserInput('/' . $this->getField($row_index, $this->options['link_field']))->setAbsolute()->toString();
+    $item->link = $this->getFieldUrl($this->getField($row_index, $this->options['link_field']))->setAbsolute()->toString();
 
     $field = $this->getField($row_index, $this->options['description_field']);
     $item->description = is_array($field) ? $field : ['#markup' => $field];
@@ -158,9 +156,7 @@ public function render($row) {
     $item_guid = $this->getField($row_index, $this->options['guid_field_options']['guid_field']);
     if ($this->options['guid_field_options']['guid_field_is_permalink']) {
       $guid_is_permalink_string = 'true';
-      // @todo Enforce GUIDs as system-generated rather than user input? See
-      //   https://www.drupal.org/node/2430589.
-      $item_guid = Url::fromUserInput('/' . $item_guid)->setAbsolute()->toString();
+      $item_guid = $this->getFieldUrl($item_guid)->setAbsolute()->toString();
     }
     $item->elements[] = [
       'key' => 'guid',
@@ -207,4 +203,42 @@ public function getField($index, $field_id) {
     return $this->view->style_plugin->getField($index, $field_id);
   }
 
+  /**
+   * Retrieves a URL from a field value.
+   *
+   * @param string $field_value
+   *   The field value retrieved with RssFields::getField().
+   *
+   * @return \Drupal\Core\Url
+   *   The URL object built from the field value.
+   */
+  protected function getFieldUrl($field_value) {
+    // @todo Views should expect and store a leading /. See:
+    //   https://www.drupal.org/node/2423913
+    return Url::fromUserInput($this->sanitizeUrlField($field_value));
+  }
+
+  /**
+   * Retrieves a URL from a field value.
+   *
+   * @param string $field_value
+   *   The field value retrieved with RssFields::getField().
+   *
+   * @return string
+   *   Sanitized user input for URL field.
+   */
+  protected function sanitizeUrlField($field_value) {
+    global $base_path;
+
+    $value = rawurldecode($field_value);
+
+    // Url::fromUserInput expects the argument to be an internal path, so the
+    // base path should be stripped if it's there.
+    if (substr($value, 0, strlen($base_path)) === $base_path) {
+      $value = substr($value, strlen($base_path));
+    }
+
+    return '/' . $value;
+  }
+
 }
diff --git a/core/modules/views/tests/modules/views_test_formatter/src/Plugin/RssFieldsWrapper.php b/core/modules/views/tests/modules/views_test_formatter/src/Plugin/RssFieldsWrapper.php
new file mode 100644
index 0000000000..ab615072aa
--- /dev/null
+++ b/core/modules/views/tests/modules/views_test_formatter/src/Plugin/RssFieldsWrapper.php
@@ -0,0 +1,16 @@
+<?php
+
+namespace Drupal\views_test_formatter\Plugin;
+
+use Drupal\views\Plugin\views\row\RssFields;
+
+/**
+ * @group views
+ */
+class RssFieldsWrapper extends RssFields {
+
+  public function testRssLink($link) {
+    return $this->sanitizeUrlField($link);
+  }
+
+}
diff --git a/core/modules/views/tests/src/Kernel/SanitizeUrlFieldTest.php b/core/modules/views/tests/src/Kernel/SanitizeUrlFieldTest.php
new file mode 100644
index 0000000000..542e118034
--- /dev/null
+++ b/core/modules/views/tests/src/Kernel/SanitizeUrlFieldTest.php
@@ -0,0 +1,28 @@
+<?php
+
+namespace Drupal\Tests\views\Kernel;
+
+use Drupal\views_test_formatter\Plugin\RssFieldsWrapper;
+
+/**
+ * Check that Rss URL field sanitizer contains one and only one slash in the beginning.
+ * @todo https://www.drupal.org/node/2423913 may make this test irrelevant.
+ *
+ * @group views
+ */
+class SanitizeUrlFieldTest extends ViewsKernelTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['system', 'views', 'views_test_formatter'];
+
+  public function testRssFields() {
+    $displayPlugin = new RssFieldsWrapper([], 'test', []);
+
+    $result = $displayPlugin->testRssLink('/<front>');
+    $this->assertTrue(substr($result, 0, 1) === '/', 'Link starts with slash');
+    $this->assertTrue(substr($result, 0, 2) !== '//', 'Link starts with only one slash');
+  }
+
+}