Revert "Remove unnecessary XSS check introduced by #2451 (#2679)"

This reverts commit c7488c7.

lib/helpers/isURLSameOrigin.js

@@ -1,6 +1,7 @@
 'use strict';
 
 var utils = require('./../utils');
+var isValidXss = require('./isValidXss');
 
 module.exports = (
   utils.isStandardBrowserEnv() ?
@@ -21,6 +22,10 @@ module.exports = (
       function resolveURL(url) {
         var href = url;
 
+        if (isValidXss(url)) {
+          throw new Error('URL contains XSS injection attempt');
+        }
+
         if (msie) {
         // IE needs attribute set twice to normalize properties
           urlParsingNode.setAttribute('href', href);

lib/helpers/isValidXss.js

@@ -0,0 +1,7 @@
+'use strict';
+
+module.exports = function isValidXss(requestURL) {
+  var xssRegex = /(\b)(on\w+)=|javascript|(<\s*)(\/*)script/gi;
+  return xssRegex.test(requestURL);
+};
+

test/specs/helpers/isURLSameOrigin.spec.js

@@ -8,4 +8,10 @@ describe('helpers::isURLSameOrigin', function () {
   it('should detect different origin', function () {
     expect(isURLSameOrigin('https://github.com/axios/axios')).toEqual(false);
   });
+
+  it('should detect XSS scripts on a same origin request', function () {
+    expect(function() {
+      isURLSameOrigin('https://github.com/axios/axios?<script>alert("hello")</script>');
+    }).toThrowError(Error, 'URL contains XSS injection attempt')
+  });  
 });

test/specs/helpers/isValidXss.spec.js

@@ -0,0 +1,25 @@
+var isValidXss = require('../../../lib/helpers/isValidXss');
+
+describe('helpers::isValidXss', function () {
+  it('should detect script tags', function () {
+    expect(isValidXss("<script/xss>alert('blah')</script/xss>")).toBe(true);
+    expect(isValidXss("<SCRIPT>alert('getting your password')</SCRIPT>")).toBe(true);
+    expect(isValidXss("<script src='http://xssinjections.com/inject.js'>xss</script>")).toBe(true);
+    expect(isValidXss("<img src='/' onerror='javascript:alert('xss')'>xss</script>")).toBe(true);
+    expect(isValidXss("<script>console.log('XSS')</script>")).toBe(true);
+    expect(isValidXss("onerror=alert('XSS')")).toBe(true);
+    expect(isValidXss("<a onclick='alert('XSS')'>Click Me</a>")).toBe(true);
+  });
+
+  it('should not detect non script tags', function() {
+    expect(isValidXss("/one/?foo=bar")).toBe(false);
+    expect(isValidXss("<safe> tags")).toBe(false);
+    expect(isValidXss("<safetag>")).toBe(false);
+    expect(isValidXss(">>> safe <<<")).toBe(false);
+    expect(isValidXss("<<< safe >>>")).toBe(false);
+    expect(isValidXss("my script rules")).toBe(false);
+    expect(isValidXss("<a notonlistener='nomatch'>")).toBe(false);
+    expect(isValidXss("<h2>MyTitle</h2>")).toBe(false);
+    expect(isValidXss("<img src='#'/>")).toBe(false);
+  })
+});