diff --git a/third_party/phpcommon b/third_party/phpcommon
index 5fb5d7f..21cbf16 160000
--- a/third_party/phpcommon
+++ b/third_party/phpcommon
@@ -1 +1 @@
-Subproject commit 5fb5d7f6fcd174b9c4ad4e30e189e90e2b8c846e
+Subproject commit 21cbf1616cd145c248452eaf77b1e1c7c14c82bd
diff --git a/webapp/index.php b/webapp/index.php
index 19efba1..7ed1cb9 100644
--- a/webapp/index.php
+++ b/webapp/index.php
@@ -16,6 +16,9 @@ spl_autoload_register('autoload_controller__');
 
 function loginVerify($accountid, $sessionid)
 {
+    if (!phpcommon\isValidSessionId($accountid, $sessionid)) {
+        return false;
+    }
     return true;
 }