Add ChangeLog entry
diff --git a/ChangeLog b/ChangeLog
index 0c579a8..7fdd90f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -21,6 +21,8 @@
    * Enable Suite B with subset of ECP curves. Make sure the code compiles even
      if some curves are not defined. Fixes #1591 reported by dbedev.
    * Fix misuse of signed arithmetic in the HAVEGE module. #2598
+   * Fix incompatibility of HMAC DRBG with Mbed TLS' own entropy module that
+     lead to HMAC DRBG seeding failure in configurations disabling SHA-512.
 
 Changes
    * Make it easier to define MBEDTLS_PARAM_FAILED as assert (which config.h