From 7b17f1f71226b2cac6b8185c8f932ed819066860 Mon Sep 17 00:00:00 2001
From: "codefix-patchflow[bot]"
 <292349666+codefix-patchflow[bot]@users.noreply.github.com>
Date: Fri, 19 Jun 2026 10:47:52 +0000
Subject: [PATCH] fix: allow protocol-less hostnames with numeric ports

---
 src/lib/isURL.js        | 4 +++-
 test/validators.test.js | 1 +
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/lib/isURL.js b/src/lib/isURL.js
index 8ae971ed6..8543f6c40 100644
--- a/src/lib/isURL.js
+++ b/src/lib/isURL.js
@@ -120,6 +120,8 @@ export default function isURL(url, options) {
         ? after_colon
         : after_colon.substring(0, first_slash_position);
       const at_position = before_slash.indexOf('@');
+      // Numeric text after the first colon is a port for protocol-less hosts.
+      const is_host_with_port = !options.require_protocol && /^[0-9]+$/.test(before_slash);
 
       if (at_position !== -1) {
         const before_at = before_slash.substring(0, at_position);
@@ -141,7 +143,7 @@ export default function isURL(url, options) {
             return false;
           }
         }
-      } else {
+      } else if (!is_host_with_port) {
         // No @ symbol, this is definitely a protocol
         url = cleanUpProtocol(potential_protocol);
 
diff --git a/test/validators.test.js b/test/validators.test.js
index 5196c6fe9..9db1f1745 100644
--- a/test/validators.test.js
+++ b/test/validators.test.js
@@ -499,6 +499,7 @@ describe('Validators', () => {
         'localhost',
         'localhost:3000',
         'service-name:8080',
+        'my-3272-service:9000',
         'https://localhost',
         'http://localhost:3000',
         'http://service-name:8080',