diff --git a/mod/forum/index.php b/mod/forum/index.php
index 59ecbb25060..64f1897b4a8 100644
--- a/mod/forum/index.php
+++ b/mod/forum/index.php
@@ -92,8 +92,13 @@
 
         foreach ($forums as $forum) {
 
-            $cm = get_coursemodule_from_instance("forum", $forum->id, $course->id);
-            $context = get_context_instance(CONTEXT_MODULE, $cm->id);
+            if (!$cm = get_coursemodule_from_instance('forum', $forum->id, $course->id)) {
+                continue;   // Shouldn't happen
+            }
+
+            if (!$context = get_context_instance(CONTEXT_MODULE, $cm->id)) {
+                continue;   // Shouldn't happen
+            }
             
             if (!has_capability('mod/forum:viewdiscussion', $context)) {
                 if (isset($forum->keyreference)) {