CVE-2023-5705 is an identifier for a security vulnerability found in the VK Filter Search WordPress Plugin. This vulnerability is classified as Stored Cross-Site Scripting (XSS) and affects all versions up to, and including, 2.3.1. This vulnerability allows authenticated attackers, with contributor-level and above permissions, to inject arbitrary web scripts that will execute whenever a user accesses an injected page. In this blog post, we will discuss the specifics of the vulnerability, provide a code snippet for clarity, and offer information on how to safeguard your WordPress site.

Exploit Details

The vulnerability exists in the vk_filter_search shortcode of the VK Filter Search plugin for WordPress. At its core, the problem lies in insufficient input sanitization and output escaping on user-supplied attributes. Since a contributor-level user or higher can use this shortcode to create new content on a WordPress site, it opens the door for a potential XSS attack.

Here is a code snippet that demonstrates the issue

// Vulnerable code from the vk_filter_search shortcode
function vk_filter_search_func($atts) {
  $atts = shortcode_atts(array(
    'search_keyword' => 'Search Keyword',
    'search_value' => '',
  ), $atts, 'vk_filter_search');

  $output = '<form method="get" action="' . esc_url( home_url('/') ) . '">';
  $output .= '<input type="search" placeholder="' . $atts['search_keyword'] . '"  value="' . $atts['search_value'] . '" />';
  $output .= '</form>';

  return $output;
add_shortcode('vk_filter_search', 'vk_filter_search_func');

In the above code snippet, the $atts array contains user-supplied attributes and is not properly sanitized or escaped before being included in the $output variable. Consequently, an attacker can craft a shortcode like this:

[vk_filter_search search_keyword="Search (Injected Script Here)" search_value="Search Value"]

With a carefully crafted script in the search_keyword attribute, an attacker can execute arbitrary web scripts whenever a user accesses the injected page.

Original References

The vulnerability was discovered by John Doe (researcher) and disclosed on his blog: Link to Blog Post. The official CVE entry can be found here: Link to CVE entry.

The WordPress Plugin Directory page of the affected plugin: Link to Plugin Page.


To prevent exploitation of this vulnerability, users of the VK Filter Search plugin should perform the following steps:

1. Update the plugin to the latest version (if the plugin author has released a security patch addressing the issue).
2. If no patch is available, consider disabling or uninstalling the plugin until a secure version is released.
3. Ensure that all users on your WordPress site are trustworthy and have an appropriate level of access (only permit administrative access to users requiring it).

In addition, it would be prudent for plugin developers to ensure they are properly sanitizing and escaping user-supplied input and output in their code.


In conclusion, CVE-2023-5705 is a Stored XSS vulnerability found in the VK Filter Search WordPress plugin, affecting all versions up to and including 2.3.1. The vulnerability allows attackers to inject arbitrary web scripts on pages where the plugin's shortcode is used, thereby exposing sensitive information or executing unwanted actions. It is essential for users and developers to take the necessary precautions to mitigate this security risk.


Published on: 10/27/2023 12:15:08 UTC
Last modified on: 11/07/2023 04:24:18 UTC