diff --git a/core/modules/link/src/Plugin/migrate/process/d6/CckLink.php b/core/modules/link/src/Plugin/migrate/process/d6/CckLink.php
index 2c03412..3b83989 100644
--- a/core/modules/link/src/Plugin/migrate/process/d6/CckLink.php
+++ b/core/modules/link/src/Plugin/migrate/process/d6/CckLink.php
@@ -66,11 +66,7 @@ protected function canonicalizeUri($uri) {
    * {@inheritdoc}
    */
   public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
-    $attributes = unserialize($value['attributes']);
-    // Drupal 6 link attributes might be double serialized.
-    if (!is_array($attributes)) {
-      $attributes = unserialize($attributes);
-    }
+    $attributes = $this->unserializeAttribute($value['attributes']);
 
     if (!$attributes) {
       $attributes = [];
@@ -83,4 +79,30 @@ public function transform($value, MigrateExecutableInterface $migrate_executable
     return $route;
   }
 
+  /**
+   * Drupal 6 link attributes might be multiply serialized.
+   *
+   * @param mixed $attributes
+   *   Variable to be processed, possibly serialized.
+   *
+   * @return array
+   *   Unserialized attributes.
+   */
+  private function unserializeAttribute($attributes) {
+    if (!is_array($attributes)) {
+      $attributes = unserialize($attributes);
+      $attributes = $this->unserializeAttribute($attributes);
+    }
+    else {
+      foreach ($attributes as &$attribute) {
+
+        if ($attribute === 'b:0;' || @unserialize($attribute) !== FALSE) {
+          $attribute = unserialize($attribute);
+          $attribute = $this->unserializeAttribute($attribute);
+        }
+      }
+    }
+    return $attributes;
+  }
+
 }