diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 69af317..bfd659e 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -4462,7 +4462,7 @@
      * params currently, and there's no 'is_init' functions for PK
      * contexts, we need to break the abstraction and peek into
      * the PK context to see if it has been initialized. */
-    if( ssl->handshake->peer_pubkey.pk_info != NULL )
+    if( ssl->handshake->peer_pubkey.pk_info != MBEDTLS_PK_INVALID_HANDLE )
         peer_pk = &ssl->handshake->peer_pubkey;
 #else /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
     if( ssl->session_negotiate->peer_cert != NULL )