Jul 142014
WordPress Plugin Name: Theme Authenticity Checker (TAC)
Plugin URL:https://wordpress.org/plugins/tac/

Plugin Author: builtBackwards
WordPress profile: builtBackwards
Plugin version: 1.5.3
Last updated: June 5, 2017 (6 years ago)
Tested up to (WP version): WP 4.8.21
Downloaded: 0
Rating: 5 (out of 5)


Scan all of your theme files for potentially malicious or unwanted code.

What TAC Does

TAC stands for Theme Authenticity Checker. TAC searches the source files of every installed theme for signs of malicious code. If such code is found, TAC displays the path to the theme file, the line number, and a small snippet of the suspect code. As of v1.3 TAC also searches for and displays static links.

Then what do you do? Just because the code is there doesn’t mean it’s not supposed to be or even qualifies as a threat, but most theme authors don’t include code outside of the WordPress scope and have no reason to obfuscate the code they make freely available to the web. We recommend contacting the theme author with the code that the script finds, as well as where you downloaded the theme.
The real value of this plugin is that you can quickly determine where code cleanup is needed in order to safely enjoy your theme.


TAC got its start when we repeatedly found obfuscated malicious code in free WordPress themes available throughout the web. A quick way to scan a theme for undesirable code was needed, so we put together this plugin.

After Googling and exploring on our own we came upon the article by Derek from 5thiryOne regarding this very subject. The deal is that many 3rd party websites are providing free WordPress themes with encoded script slipped in – some even going as far as to claim that decoding the gibberish constitutes breaking copyright law. The encoded script may contain a variety of undesirable payloads, such as promoting third party sites or even hijack attempts.


Installation Instructions

After downloading and extracting the latest version of TAC:

  1. Upload tac.php to the /wp-content/plugins/ directory
  2. Activate the plugin through the ‘Plugins’ menu in WordPress
  3. Go to Appearance -> TAC in the WordPress Admin
  4. The results of the scan will be displayed for each theme with the filename and line number of any threats.
  5. You can click on the path to the theme file to edit in the WordPress Theme Editor

What if I find something?

Contact the theme’s original author to double check if that section of code is supposed to be in the theme in the first place – chances are it shouldn’t as there isn’t a logical reason have obfuscated code in a theme.

If something is malicious or simply unwanted, TAC tells you what file to edit, you can even just click on the file path to be taken straight to the WordPress Theme Editor.

Why does TAC list static links?

First of all, static links aren’t necessarily bad, TAC just lists them so you can quickly see where your theme is linking to.

What about future vulnerabilities?

As we find them we will add them to TAC. If you find one, PLEASE let us know:
Contact builtBackwards or post in the WordPress.org Forum


  1. TAC Report Page

    TAC Report Page

Other notes:

Latest Change log entry:


admin, javascript, security, theme authentication, themes

+ Jason's Comments

For scanning of themes, I recommend for extra security, Theme Authenticity Checker plugin, which can find suspicious or malicious code and embedded outgoings links. TAC plugin found code which Wordfence security didn’t.

Use WordPress Health Check for an overview of update and security issues.

Read up on other WordPress security related plugins and strategies.

Website Optimization and Maintenance

There are a few ways to optimize and speed up your website for viewers and search engines: database clean up, image optimization, page / script compression, CPU / server load optimization, server file caching and utilize browser caching.

I provide website tune ups on request and recommend a schedule for Search Engine Optimization (SEO) and Page Speed optimization.

Optimization is best applied together with website security and protection and backup and maintenance.