diff --git a/mod/forum/lib.php b/mod/forum/lib.php
index 2146cf7f37f..140390dac01 100644
--- a/mod/forum/lib.php
+++ b/mod/forum/lib.php
@@ -81,6 +81,9 @@ if (!isset($CFG->forum_enabletimedposts)) {   // Newish feature that is not quit
     $CFG->forum_enabletimedposts = false;
 }
 
+if (!isset($CFG->forum_enablerssfeeds)) {   // Disable forum RSS feeds by default
+    $CFG->forum_enablerssfeeds = false;
+}
 
 /// STANDARD FUNCTIONS ///////////////////////////////////////////////////////////