diff --git a/src/lib/isHexColor.js b/src/lib/isHexColor.js
index b7a2e5a23..34903f413 100644
--- a/src/lib/isHexColor.js
+++ b/src/lib/isHexColor.js
@@ -11,6 +11,7 @@ const default_is_hexcolor_options = {
 export default function isHexColor(str, options) {
   assertString(str);
   options = merge(options, default_is_hexcolor_options);
+
   const hexcolor_regex = options.require_hashtag
     ? hexcolor_with_prefix
     : hexcolor;
diff --git a/src/lib/util/merge.js b/src/lib/util/merge.js
index 071477696..d50329b56 100644
--- a/src/lib/util/merge.js
+++ b/src/lib/util/merge.js
@@ -1,4 +1,7 @@
 export default function merge(obj = { }, defaults) {
+  if (typeof obj !== 'object' || obj === null) {
+    obj = {};
+  }
   for (const key in defaults) {
     if (typeof obj[key] === 'undefined') {
       obj[key] = defaults[key];
diff --git a/test/validators.test.js b/test/validators.test.js
index 9bd00d6ec..b5a6be4c5 100644
--- a/test/validators.test.js
+++ b/test/validators.test.js
@@ -2,6 +2,7 @@ import assert from 'assert';
 import fs from 'fs';
 import timezone_mock from 'timezone-mock';
 import vm from 'vm';
+import validator from '../index';
 import test from './testFunctions';
 
 let validator_js = fs.readFileSync(require.resolve('../validator.js')).toString();
@@ -5041,6 +5042,20 @@ describe('Validators', () => {
         '',
       ],
     });
+    test({
+      validator: 'isHexColor',
+      args: [null],
+      valid: ['#fff', '#000000', '123'],
+      invalid: ['not-a-color'],
+    });
+    test({
+      validator: 'isHexColor',
+      args: [123],
+      valid: ['#fff', '#000000', '123', 'abc'],
+      invalid: ['gray', 'not-a-color'],
+    });
+    const validColors = ['#ff0034', '#CCCCCC'].filter(validator.isHexColor);
+    assert.strictEqual(validColors.length, 2);
   });
 
   it('should validate HSL color strings', () => {