diff --git a/ChangeLog.txt b/ChangeLog.txt
index 0110aede..152e634f 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -4,6 +4,8 @@ Broker:
 - Fix memory leak if a client provided a username/password for a listener with
   use_identity_as_username configured.
 - Fix use_identity_as_username not working on websockets clients.
+- Don't crash if an auth plugin returns MOSQ_ERR_AUTH for a username check on
+  a websockets client. Closes #490.
 
 Client library:
 - Fix incorrect PSK key being used if it had leading zeroes.
diff --git a/lib/net_mosq.c b/lib/net_mosq.c
index 063c4a22..c51749c3 100644
--- a/lib/net_mosq.c
+++ b/lib/net_mosq.c
@@ -214,14 +214,19 @@ int _mosquitto_socket_close(struct mosquitto *mosq)
 
 	assert(mosq);
 #ifdef WITH_TLS
-	if(mosq->ssl){
-		SSL_shutdown(mosq->ssl);
-		SSL_free(mosq->ssl);
-		mosq->ssl = NULL;
-	}
-	if(mosq->ssl_ctx){
-		SSL_CTX_free(mosq->ssl_ctx);
-		mosq->ssl_ctx = NULL;
+#ifdef WITH_WEBSOCKETS
+	if(!mosq->wsi)
+#endif
+	{
+		if(mosq->ssl){
+			SSL_shutdown(mosq->ssl);
+			SSL_free(mosq->ssl);
+			mosq->ssl = NULL;
+		}
+		if(mosq->ssl_ctx){
+			SSL_CTX_free(mosq->ssl_ctx);
+			mosq->ssl_ctx = NULL;
+		}
 	}
 #endif