CVE-2026-96256 describes a stored cross-site scripting vulnerability in the Gutenberg Essential Blocks – Page Builder for Gutenberg Blocks & Patterns plugin for WordPress, affecting versions up to and including 6.4.5. The flaw is due to improper neutralization of input in the Google Map block's 'marker' attribute, where marker title and content values are insufficiently sanitized and escaped. These values are stored as JSON and decoded, then concatenated directly into raw HTML by the frontend InfoWindow content builder script. This allows authenticated attackers with Contributor-level permissions or higher to inject malicious scripts that execute in the context of any user viewing the compromised page.

An attacker with Contributor-level or higher access can inject arbitrary JavaScript into pages via the Google Map block's marker attribute. This script executes in the context of users visiting the page, potentially leading to session hijacking, defacement, or other client-side attacks. The vulnerability does not affect unauthenticated users directly but leverages authenticated user privileges to persist malicious code.

No explicit patch or fix is provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict Contributor-level access to trusted users and consider disabling or avoiding use of the Google Map block's marker feature. Monitor vendor channels for updates and apply official patches once released.