diff --git a/ChangeLog b/ChangeLog
index cf7d13a..25f3b32 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,7 +14,9 @@
      facilitate testing and maintenance.
 
 Features
-    * Implement HKDF per RFC 5869. Contributed by Thomas Fossati.
+   * Implement HKDF per RFC 5869. Contributed by Thomas Fossati.
+   * Add additional block mode, OFB (Output Feedback), to the AES module and
+     cipher abstraction module.
 
 = mbed TLS 2.9.0 branch released 2018-04-30