diff --git a/history.txt b/history.txt
index 6016010510e..67d043213f1 100644
--- a/history.txt
+++ b/history.txt
@@ -1,6 +1,14 @@
 OMERO version history
 =====================
 
+5.3.5 (October 2017)
+--------------------
+
+This is a security release - see the
+:secvuln:`security advisory <2017-SV4-guest-user>` for further details.
+
+It is highly recommended that you upgrade your server.
+
 5.3.4 (September 2017)
 ----------------------