What the vulnerability does
01Description
The FastSpring plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'fastspring/block-fastspringblocks-complete-product-catalog' block in all versions up to, and including, 3.0.1 due to insufficient input sanitization and output escaping on the 'color' attribute. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Explanation of Vulnerability in Simple Terms
02Summary
FastSpring versions up to 3.0.1 contain a cross-site scripting (XSS) vulnerability that allows authenticated users to inject malicious scripts affecting other users. The vulnerability has a changed scope, meaning the impact extends beyond the vulnerable component itself. Low-privileged users can exploit this without additional user interaction to compromise site integrity and confidentiality.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that execute in other users' browsers, potentially stealing data or performing actions on their behalf.
Potential impact on your site
04Site Impact
Authenticated users can inject scripts affecting other site visitors, risking data theft, session hijacking, or malware distribution.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege account on the site; no user interaction required from victims.
Key dates
06Disclosure timeline
May 31, 2025
CVE published
April 8, 2026
Record updated
