What the vulnerability does
01Description
The Page Builder Gutenberg Blocks – CoBlocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via external iCal feed data in all versions up to, and including, 3.1.16 due to insufficient output escaping of event titles, descriptions, and locations fetched from external iCal feeds in the Events block rendering function. 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
CoBlocks, a WordPress page builder plugin, contains a stored cross-site scripting (XSS) vulnerability in versions up to 3.1.16. An authenticated user with low privileges can inject malicious scripts that execute in the browsers of other site users, including administrators. The vulnerability affects the entire site scope due to how the plugin processes and stores user input.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that run in other users' browsers, potentially stealing credentials or performing actions as those users.
Potential impact on your site
04Site Impact
Any authenticated user can compromise other users' sessions or steal admin credentials through stored XSS attacks.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege WordPress account (e.g., contributor or editor role).
Key dates
06Disclosure timeline
April 18, 2026
CVE published
April 20, 2026
Record updated
