CVE-2025-15690 Overview
CVE-2025-15690 is a Stored Cross-Site Scripting (XSS) vulnerability in the Content Mask WordPress plugin before version 1.8.5.6. The plugin fails to sanitise and escape post content before rendering it on generated pages. Authenticated users holding a role as low as Contributor can inject persistent JavaScript payloads. The payloads execute in the browser of any user who views or previews the affected page, including administrators. The plugin's role-restriction option does not block this attack path.
Critical Impact
A Contributor-level account can plant persistent JavaScript that runs against higher-privileged users, enabling session theft, forced actions, and further site compromise.
Affected Products
- Content Mask WordPress plugin versions prior to 1.8.5.6
- WordPress sites permitting Contributor-level accounts to submit posts through the plugin
- Any WordPress installation exposing pages generated by the vulnerable plugin
Discovery Timeline
- 2026-09-09 - CVE-2025-15690 published to NVD
- 2026-09-09 - Last updated in NVD database
Technical Details for CVE-2025-15690
Vulnerability Analysis
The vulnerability is a stored XSS flaw classified under [CWE-79]. The Content Mask plugin ingests post content submitted by authenticated users and later renders it on pages generated for masked URLs. The output routine does not apply WordPress escaping functions such as esc_html(), esc_attr(), or wp_kses_post() to untrusted fields before echoing them into the page markup.
Because the flaw persists server-side, the injected script runs every time the affected page is viewed or previewed. Administrators previewing Contributor drafts, or any visitor loading a masked page, execute the attacker-controlled payload in their authenticated browser session.
Root Cause
The root cause is missing output sanitisation and escaping in the plugin's page-generation logic. Content submitted with a post is written back to the response without contextual encoding. The plugin's role-based restriction setting, which is intended to gate who can use Content Mask features, does not filter the payload and therefore does not mitigate the injection.
Attack Vector
An attacker first obtains or registers a Contributor account on a WordPress site running the vulnerable plugin. The attacker creates or edits a post containing a JavaScript payload in a field consumed by Content Mask. When an editor, administrator, or site visitor views or previews the resulting page, the payload executes in their session context. Outcomes include cookie theft, administrator account takeover through forged requests, and injection of persistent backdoors into the site.
No verified public exploit code is available. See the WPScan Vulnerability Report for technical details.
Detection Methods for CVE-2025-15690
Indicators of Compromise
- Post content or Content Mask fields containing <script> tags, onerror=, onload=, or javascript: URI schemes submitted by Contributor-level accounts.
- Unexpected outbound requests from administrator browsers to attacker-controlled domains after viewing or previewing posts.
- New administrator accounts, modified user roles, or unexpected plugin installations following preview activity on Contributor drafts.
Detection Strategies
- Audit the WordPress wp_posts table for post content and meta values containing script tags or event handler attributes.
- Review web server access logs for POST requests to /wp-admin/post.php and /wp-admin/admin-ajax.php from Contributor accounts that include HTML or script payloads.
- Monitor Content Security Policy (CSP) violation reports on pages generated by the Content Mask plugin.
Monitoring Recommendations
- Alert on creation or role change of administrator accounts that occur shortly after preview or view activity on Contributor-authored content.
- Track installation of the Content Mask plugin across managed WordPress sites and flag versions prior to 1.8.5.6.
- Enable WordPress audit logging plugins to record post edits, user role assignments, and plugin changes for forensic review.
How to Mitigate CVE-2025-15690
Immediate Actions Required
- Update the Content Mask plugin to version 1.8.5.6 or later on every WordPress installation.
- Review recent Contributor and Author submissions for embedded script content and remove any suspicious posts.
- Rotate administrator passwords and invalidate active sessions if untrusted preview activity has occurred.
Patch Information
The vendor addressed the issue in Content Mask version 1.8.5.6 by adding proper sanitisation and escaping of post-supplied content before output. Refer to the WPScan Vulnerability Report for advisory details and fix references.
Workarounds
- Deactivate the Content Mask plugin until the site is upgraded to 1.8.5.6 or later.
- Restrict Contributor and Author registration, and require editorial review before any draft is previewed by administrators.
- Deploy a Web Application Firewall (WAF) rule to block requests containing script tags or event handler attributes in Content Mask fields.
# Update Content Mask via WP-CLI to the patched version
wp plugin update content-mask --version=1.8.5.6
# Verify installed version
wp plugin get content-mask --field=version
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
