diff --git a/ChangeLog b/ChangeLog
index fe5ce6535..15b555773 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS 2.1.x branch released xxxx-xx-xx
+
+Security
+   * Add exponent blinding to RSA private operations as a countermeasure
+     against side-channel attacks like the cache attack described in
+     https://arxiv.org/abs/1702.08719v2.
+     Found and fix proposed by Michael Schwarz, Samuel Weiser, Daniel Gruss,
+     Clémentine Maurice and Stefan Mangard.
+
 = mbed TLS 2.1.7 branch released 2017-03-08
 
 Security