diff --git a/pjnath/src/pjnath/stun_sock.c b/pjnath/src/pjnath/stun_sock.c
index f6b8789..7f6aacd 100644
--- a/pjnath/src/pjnath/stun_sock.c
+++ b/pjnath/src/pjnath/stun_sock.c
@@ -832,6 +832,8 @@
     pj_stun_sock *stun_sock;
 
     stun_sock = (pj_stun_sock*) pj_activesock_get_user_data(asock);
+    if (!stun_sock)
+	return PJ_FALSE;
 
     /* Don't report to callback if this is internal message */
     if (send_key == &stun_sock->int_send_key) {