diff --git a/Xext/xres.c b/Xext/xres.c
index 8aa1588a1..79b9b116b 100644
--- a/Xext/xres.c
+++ b/Xext/xres.c
@@ -309,7 +309,9 @@ ProcXResQueryClientResources(ClientPtr client)
 
     clientID = CLIENT_ID(stuff->xid);
 
-    if ((clientID >= currentMaxClients) || !clients[clientID]) {
+    if ((clientID >= currentMaxClients) || !clients[clientID] ||
+        (XaceHookClientAccess(client, clients[clientID], DixReadAccess)
+                              != Success)) {
         client->errorValue = stuff->xid;
         return BadValue;
     }