CVE-2026-107864

Unauthenticated XSS attack in Ad Inserter plugin up to version 2.8.18. An attacker can inject malicious script without authentication.

The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress up to version 2.8.18 contains a sensitive information exposure vulnerability via ai_wp_footer_hook. This allows authenticated attackers with subscriber-level access and above to extract data such as the server's internal IP address, PHP configuration, WordPress and theme versions, hardening constants, the plugin's full block matrix, and all post meta values including underscore-prefixed protected keys such as API tokens and private integration state written by other plugins.

The Ad Inserter plugin for WordPress up to version 2.8.18 is vulnerable to Reflected XSS via the 's' search parameter. Insufficient input sanitization and output escaping allow unauthenticated attackers to inject arbitrary web scripts that execute when a user clicks a crafted link. Exploitation requires an ad block with {title} or {short-title} placeholder enabled on search pages.

The Ad Inserter plugin for WordPress up to version 2.8.18 is vulnerable to Reflected XSS via the Referer header. Insufficient input sanitization and output escaping on the '{search-query}' dynamic tag allow unauthenticated attackers to execute arbitrary JavaScript in the context of the site for any visitor, including a signed-in administrator. Exploitation requires an ad block with the '{search-query}' tag and automatic insertion enabled.

The Ad Inserter WordPress plugin before 2.8.19 does not correctly restrict access to one of its settings pages, making it reachable by every logged-in user under a configuration its own settings allow, and does not filter the content saved there. This allows users with a role as low as subscriber to store code which is then executed as PHP or served unescaped to site visitors.

The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress (all versions up to and including 2.8.16) is vulnerable to authorization bypass due to a missing capability check on the 'ai-debug-code' URL parameter. An unauthenticated attacker can view administrator-configured header and footer code blocks that have been disabled from public display.

The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.8.16 due to a missing capability check in the `ai_ajax` function. This makes it possible for unauthenticated attackers to view the contents of ad blocks that an administrator has restricted to administrator-only visibility.

The Ad Inserter WordPress plugin version 2.8.11 and earlier contains a Cross-site Scripting (XSS) vulnerability due to improper input neutralization during web page generation. The flaw allows an attacker to exploit incorrectly configured access control security levels.