diff --git a/availability/classes/info_module.php b/availability/classes/info_module.php
index 201b7dc13af..83403455529 100644
--- a/availability/classes/info_module.php
+++ b/availability/classes/info_module.php
@@ -180,7 +180,12 @@ class info_module extends info {
             if (is_object($cmorid)) {
                 $cmorid = $cmorid->id;
             }
-            $cm = $DB->get_record('course_modules', array('id' => $cmorid), '*', MUST_EXIST);
+            $cm = $DB->get_record('course_modules', array('id' => $cmorid));
+            if (!$cm) {
+                // In some error cases, the course module may not exist.
+                debugging('info_module::is_user_visible called with invalid cmid ' . $cmorid, DEBUG_DEVELOPER);
+                return false;
+            }
         }
 
         // If requested, check user can access the course.