# UNDF: UNDF-2026-000000053
--- a/src/lib-storage/mail-storage-hooks.c
+++ b/src/lib-storage/mail-storage-hooks.c
@@ -119,12 +119,21 @@ static void mail_user_add_plugin_hooks(struct mail_user *user)
 	const struct mail_storage_module_hooks *module_hook;
 	ARRAY(struct mail_storage_module_hooks) tmp_hooks;
 	const char *name;
+	ARRAY_TYPE(const_string) sorted_plugins;
+
+	/* Build a sorted copy of mail_plugins for O(log P) binary search.
+	   Avoids O(H×P) from array_lsearch inside the array_foreach loop
+	   (H = module_hooks count, P = mail_plugins count). */
+	if (array_is_created(&user->set->mail_plugins)) {
+		t_array_init(&sorted_plugins, array_count(&user->set->mail_plugins));
+		array_append_array(&sorted_plugins, &user->set->mail_plugins);
+		array_sort(&sorted_plugins, i_strcmp_p);
+	}

 	/* first get all hooks wanted by the user */
 	t_array_init(&tmp_hooks, array_count(&module_hooks));
 	array_foreach(&module_hooks, module_hook) {
 		if (!module_hook->forced) {
 			name = module_get_plugin_name(module_hook->module);
 			if (!array_is_created(&user->set->mail_plugins) ||
-			    array_lsearch(&user->set->mail_plugins, &name,
-					  i_strcmp_p) == NULL)
+			    array_bsearch(&sorted_plugins, &name,
+					  i_strcmp_p) == NULL)
 				continue;
 		}
 		array_push_back(&tmp_hooks, module_hook);