diff --git a/ChangeLog b/ChangeLog
index f96786d72..c7b39c9b6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS 2.4.x branch released 2016-xx-xx
+
+Security
+   * Removed MD5 from the allowed hash algorithms for CertificateRequest and
+     CertificateVerify messages, to prevent SLOTH attacks against TLS 1.2.
+
 = mbed TLS 2.4.0 branch released 2016-10-17
 
 Security
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 84a04ae53..ee3cadb02 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -7644,8 +7644,7 @@ int mbedtls_ssl_set_calc_verify_md( mbedtls_ssl_context *ssl, int md )
 #if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
 #if defined(MBEDTLS_MD5_C)
         case MBEDTLS_SSL_HASH_MD5:
-            ssl->handshake->calc_verify = ssl_calc_verify_tls;
-            break;
+            return MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH;
 #endif
 #if defined(MBEDTLS_SHA1_C)
         case MBEDTLS_SSL_HASH_SHA1: