Input validation vulnerability in Inline Related Posts 3.4.0

The plugin called Inline Related Posts on WordPress has a security issue that makes it vulnerable to a type of attack called Stored Cross-Site Scripting. This is because it does not properly clean up or protect the information that is entered into the admin settings. This can allow someone who is logged in as an administrator or higher to add their own code to a page, which will then run whenever someone visits that page. This only affects websites that have multiple sites or have disabled a security feature called unfiltered_html.