CVE-2026-15101: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in wpbakery WPBakery Page Builder

CVE-2026-15101 is a stored cross-site scripting vulnerability in WPBakery Page Builder for WordPress, affecting all versions up to and including 8.7.4. The issue is due to insufficient input sanitization and output escaping of the 'data' parameter. Although wp_kses_post sanitization is applied during content saving, it fails to neutralize base64-encoded malicious scripts that contain no HTML tags. These payloads are decoded and echoed unescaped by the vc_raw_html shortcode template when rendering the page, allowing authenticated attackers with subscriber-level privileges or higher to inject arbitrary scripts that execute in the context of any user viewing the page.

An attacker with subscriber-level or higher access can inject persistent malicious scripts into pages, which execute in the browsers of users who visit those pages. This can lead to information disclosure and integrity impacts, such as theft of user credentials or session tokens, and manipulation of page content. The vulnerability does not affect availability.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict subscriber-level access to trusted users only and consider disabling or limiting use of the 'data' parameter or the vc_raw_html shortcode if possible. Monitor official WPBakery communications for updates and apply any official patches promptly once released.