diff --git a/components/mbedtls/library/ssl_cli.c b/components/mbedtls/library/ssl_cli.c
index a2b9f8cfe..99f492819 100644
--- a/components/mbedtls/library/ssl_cli.c
+++ b/components/mbedtls/library/ssl_cli.c
@@ -2049,10 +2049,16 @@ static int ssl_parse_server_psk_hint( mbedtls_ssl_context *ssl,
      *
      * opaque psk_identity_hint<0..2^16-1>;
      */
+    if( (*p) > end - 2 )
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message "
+                                    "(psk_identity_hint length)" ) );
+        return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
+    }
     len = (*p)[0] << 8 | (*p)[1];
     *p += 2;
 
-    if( (*p) + len > end )
+    if( (*p) > end - len )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message "
                                     "(psk_identity_hint length)" ) );
@@ -2470,10 +2476,18 @@ static int ssl_parse_server_key_exchange( mbedtls_ssl_context *ssl )
         /*
          * Read signature
          */
+
+        if( p > end - 2 )
+        {
+            MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
+            mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                            MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
+            return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
+        }
         sig_len = ( p[0] << 8 ) | p[1];
         p += 2;
 
-        if( end != p + sig_len )
+        if( p != end - sig_len )
         {
             MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
             mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
diff --git a/components/mbedtls/library/ssl_srv.c b/components/mbedtls/library/ssl_srv.c
index f137c3dce..97d7a9e80 100644
--- a/components/mbedtls/library/ssl_srv.c
+++ b/components/mbedtls/library/ssl_srv.c
@@ -3436,7 +3436,7 @@ static int ssl_parse_client_psk_identity( mbedtls_ssl_context *ssl, unsigned cha
     /*
      * Receive client pre-shared key identity name
      */
-    if( *p + 2 > end )
+    if( end - *p < 2 )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) );
         return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE );
@@ -3445,7 +3445,7 @@ static int ssl_parse_client_psk_identity( mbedtls_ssl_context *ssl, unsigned cha
     n = ( (*p)[0] << 8 ) | (*p)[1];
     *p += 2;
 
-    if( n < 1 || n > 65535 || *p + n > end )
+    if( n < 1 || n > 65535 || n > (size_t) ( end - *p ) )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) );
         return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE );
diff --git a/components/mbedtls/port/include/mbedtls/esp_config.h b/components/mbedtls/port/include/mbedtls/esp_config.h
index c81bf1a06..b844dcef9 100644
--- a/components/mbedtls/port/include/mbedtls/esp_config.h
+++ b/components/mbedtls/port/include/mbedtls/esp_config.h
@@ -926,7 +926,7 @@
  *
  * This enables support for RSAES-OAEP and RSASSA-PSS operations.
  */
-#define MBEDTLS_PKCS1_V21
+//#define MBEDTLS_PKCS1_V21
 
 /**
  * \def MBEDTLS_RSA_NO_CRT
@@ -1326,7 +1326,7 @@
  *
  * Comment this macro to disable support for truncated HMAC in SSL
  */
-#define MBEDTLS_SSL_TRUNCATED_HMAC
+//#define MBEDTLS_SSL_TRUNCATED_HMAC
 
 /**
  * \def MBEDTLS_THREADING_ALT
@@ -1420,7 +1420,7 @@
  *
  * Comment this macro to disallow using RSASSA-PSS in certificates.
  */
-#define MBEDTLS_X509_RSASSA_PSS_SUPPORT
+//#define MBEDTLS_X509_RSASSA_PSS_SUPPORT
 
 /**
  * \def MBEDTLS_ZLIB_SUPPORT