diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 54129891a7..2b8f8919c5 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -954,6 +954,8 @@ void mbedtls_ssl_transform_init(mbedtls_ssl_transform *transform)
 void mbedtls_ssl_session_init(mbedtls_ssl_session *session)
 {
     memset(session, 0, sizeof(mbedtls_ssl_session));
+    /* Set verify_result to indicate failure by default. */
+    session->verify_result = MBEDTLS_X509_VERIFY_NOT_STARTED;
 }
 
 MBEDTLS_CHECK_RETURN_CRITICAL