diff --git a/src/bio.c b/src/bio.c
index 595343488..5f845cf0b 100644
--- a/src/bio.c
+++ b/src/bio.c
@@ -2375,6 +2375,7 @@ int wolfSSL_BIO_flush(WOLFSSL_BIO* bio)
         if (err == 1) {
             wolfSSL_free(ssl);
             wolfSSL_BIO_free(sslBio);
+            sslBio = NULL;
             wolfSSL_BIO_free(connBio);
         }