The Relevanssi – A Better Search plugin for WordPress is vulnerable to CSV Injection in all versions up to, and including, 4.22.1. This makes it possible for unauthenticated attackers to embed untrusted input into exported CSV files, which can result in code execution when these files are downloaded and opened on a local system with a vulnerable configuration.

The Relevanssi – A Better Search plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the relevanssiupdatecounts() function in all versions up to, and including, 4.22.1. This makes it possible for unauthenticated attackers to execute expensive queries on the application that could lead into DOS.

The Relevanssi – A Better Search plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 4.28.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is only exploitable when the administrator has configured a non-empty value for the "Allowable tags in excerpts" setting, such as the default example value of <p><a><strong>, as the prefix-matching regex must have an allowable tag whose name is a prefix of the injected tag name.