FastSpring WordPress Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the FastSpring plugin for WordPress, affecting all versions through 3.0.1. The issue arises in the 'fastspring/block-fastspringblocks-complete-product-catalog' block, where inadequate input sanitization and output escaping of the 'color' attribute allow authenticated attackers with contributor-level access or higher to inject arbitrary scripts. These scripts are executed when a user accesses the compromised page.

Impact

Exploitation of this vulnerability allows for stored cross-site scripting, where injected scripts are executed in the context of the user viewing the page.