diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index 386a754..c6bb770 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -1379,6 +1379,12 @@
 
     MBEDTLS_SSL_DEBUG_MSG(2, ("=> write change cipher spec"));
 
+    /* Only one CCS to send. */
+    if (ssl->handshake->ccs_count > 0) {
+        ret = 0;
+        goto cleanup;
+    }
+
     /* Write CCS message */
     MBEDTLS_SSL_PROC_CHK(ssl_tls13_write_change_cipher_spec_body(
                              ssl, ssl->out_msg,