diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 48d0a03dc..6579c9686 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -3627,7 +3627,7 @@ MBEDTLS_CHECK_RETURN_CRITICAL
 static int ssl_handle_possible_reconnect(mbedtls_ssl_context *ssl)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t len;
+    size_t len = 0;
 
     if (ssl->conf->f_cookie_write == NULL ||
         ssl->conf->f_cookie_check == NULL) {