diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index c8ffc1e..2726cbc 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -1546,8 +1546,16 @@
 
 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_STREAM)
     if (ssl_mode == MBEDTLS_SSL_MODE_STREAM) {
+        if (rec->data_len < transform->maclen) {
+            MBEDTLS_SSL_DEBUG_MSG(1,
+                                  ("Record too short for MAC:"
+                                   " %" MBEDTLS_PRINTF_SIZET " < %" MBEDTLS_PRINTF_SIZET,
+                                   rec->data_len, transform->maclen));
+            return MBEDTLS_ERR_SSL_INVALID_MAC;
+        }
+
         /* The only supported stream cipher is "NULL",
-         * so there's nothing to do here.*/
+         * so there's no encryption to do here.*/
     } else
 #endif /* MBEDTLS_SSL_SOME_SUITES_USE_STREAM */
 #if defined(MBEDTLS_GCM_C) || \
@@ -2010,7 +2018,7 @@
         unsigned char mac_expect[MBEDTLS_SSL_MAC_ADD] = { 0 };
         unsigned char mac_peer[MBEDTLS_SSL_MAC_ADD] = { 0 };
 
-        /* If the initial value of padlen was such that
+        /* For CBC+MAC, If the initial value of padlen was such that
          * data_len < maclen + padlen + 1, then padlen
          * got reset to 1, and the initial check
          * data_len >= minlen + maclen + 1
@@ -2022,6 +2030,9 @@
          * subtracted either padlen + 1 (if the padding was correct)
          * or 0 (if the padding was incorrect) since then,
          * hence data_len >= maclen in any case.
+         *
+         * For stream ciphers, we checked above that
+         * data_len >= maclen.
          */
         rec->data_len -= transform->maclen;
         ssl_extract_add_data_from_record(add_data, &add_data_len, rec,