Fix cumulative greeting message for custom greetings

Changes.md

@@ -25,6 +25,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/).
 - fix(outbound): in outbound hook_delivered, when mx.exchange contains
   an IP, use mx.from_dns
 - fix(bin/haraka): fix for finding path to config/docs/Plugins.md
+- fix(connections): fix for infinitely expanding custom greeting #3446
 
 ### [3.0.5] - 2024-09-27
 

connection.js

@@ -783,10 +783,11 @@
                 });
                 break;
             default: {
-                let greeting = cfg.message.greeting;
-                if (greeting?.length) {
+                let greeting;
+                if (cfg.message.greeting?.length) {
                     // RFC5321 section 4.2
                     // Hostname/domain should appear after the 220
+                    greeting = [...cfg.message.greeting];
                     greeting[0] = `${this.local.host} ESMTP ${greeting[0]}`;
                     if (cfg.uuid.banner_chars) {
                         greeting[0] += ` (${this.uuid.substr(0, cfg.uuid.banner_chars)})`;