Zero-Day Advisory

Fortinet Discovers WordPress Beaver Builder Plugin Cross-Site Scripting Vulnerability

Summary

Fortinet's FortiGuard Labs has discovered a Stored Cross Site Scripting vulnerability in the WordPress Beaver Builder Plugin.


Beaver Builder is a flexible drag and drop page builder that works on the front end of your WordPress website.


The Beaver Builder is vulnerable to Stored Cross-Site Scripting via the 'caption' parameter added to images via the media uploader due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers with access to the Beaver Builder editor and the ability to upload media files to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Solutions

FortiGuard Labs released the following FortiGate IPS signature which covers this specific vulnerability:

WordPress.Plugin.Beaver.Builder.Image.Caption.XSS
Released Aug 17, 2022

Users should apply the solution provided by The Beaver Builder Team.

Timeline

Fortinet reported the vulnerability to The Beaver Builder Team on June 05, 2020

The Beaver Builder Team confirmed the vulnerability on June 07, 2020

The Beaver Builder Team patched the vulnerability on August 09, 2022

Acknowledgement

This vulnerability was discovered by Vishnupriya Ilango & Zhouyuan Yang of Fortinet's FortiGuard Labs.

IPS Subscription

Fortinet customers who subscribe to Fortinet's intrusion prevention (IPS) service should be protected against this vulnerability with the appropriate configuration parameters in place. Fortinet's IPS service is one component of FortiGuard Subscription Services, which also offer comprehensive solutions such as antivirus, Web content filtering and antispam capabilities. These services enable protection against threats on both application and network layers. FortiGuard Services are continuously updated by FortiGuard Labs, which enables Fortinet to deliver a combination of multi-layered security intelligence and true zero-day protection from new and emerging threats. These updates are delivered to all FortiGate, FortiMail and FortiClient products. Fortinet strictly follows responsible disclosure guidelines to ensure optimum protection during a threat's lifecycle.