What the vulnerability does
01Description
The Sherk Custom Post Type Displays plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'title' shortcode attribute in all versions up to, and including, 1.2.1. This is due to insufficient input sanitization and output escaping on the 'title' attribute of the 'sherkcptdisplays' shortcode. Specifically, in the sherkcptdisplays_func() function in includes/SherkCPTDisplaysShortcode.php, the 'title' attribute value is extracted from shortcode_atts() on line 19 and directly concatenated into an HTML <h2> tag on line 31 without any escaping. 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
Sherk Custom Post Type Displays versions 1.2.1 and earlier contain a cross-site scripting (XSS) vulnerability. An authenticated user with low privileges can inject malicious scripts that execute in other users' browsers, including administrators. The vulnerability has scope change, meaning the impact extends beyond the vulnerable component itself.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that run in other users' browsers, potentially stealing session tokens or performing actions as those users.
Potential impact on your site
04Site Impact
Any authenticated user can compromise admin accounts or other users' sessions through stored or reflected XSS attacks.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege account on the site; no user interaction required from the victim.
Key dates
06Disclosure timeline
March 21, 2026
CVE published
April 8, 2026
Record updated
