CVE-2025-9044: Mapster WP Maps Plugin XSS Vulnerability

CVE-2025-9044 Overview

CVE-2025-9044 is a Stored Cross-Site Scripting (XSS) vulnerability in the Mapster WP Maps plugin for WordPress. The flaw affects all versions up to and including 1.20.0. It stems from insufficient input sanitization and output escaping across multiple plugin fields. Authenticated users with contributor-level permissions or above can inject arbitrary JavaScript into pages. The injected scripts execute in the browser of any visitor who views an affected page. The issue is tracked under CWE-79.

Critical Impact
Authenticated contributors can plant persistent JavaScript payloads that run against site visitors and administrators, enabling session theft, forced actions, and defacement.

Affected Products

Mapster WP Maps plugin for WordPress — versions up to and including 1.20.0
WordPress sites allowing contributor-level accounts or higher to interact with the plugin
Any downstream environment bundling the vulnerable plugin version

Discovery Timeline

2025-09-26 - CVE-2025-9044 published to NVD
2026-10-11 - Last updated in NVD database

Technical Details for CVE-2025-9044

Vulnerability Analysis

The plugin fails to sanitize user-supplied input and does not escape output rendered from multiple map configuration fields. A contributor-level account can submit crafted values containing HTML or JavaScript. Those values are stored in the database and later rendered to any user who loads the affected page. Because the payload persists server-side, every visitor to the compromised page triggers execution. The scope change in the attack path indicates that the injected script can affect resources beyond the vulnerable component, including administrator sessions. See the Wordfence Vulnerability Report for additional context.

Root Cause

The root cause is missing input validation combined with missing output escaping in the ACF map field handlers. The vulnerable code paths are visible in the plugin source at admin/includes/acf-map-fields.php, specifically around the field rendering functions. Values submitted through those fields are written to post metadata and later echoed into page markup without calls to WordPress escaping helpers such as esc_html(), esc_attr(), or wp_kses_post().

Attack Vector

Exploitation requires an authenticated session at the contributor role or higher. The attacker edits a post or map entity and places a JavaScript payload into one of the affected plugin fields. The payload is stored in the database. When any user — including authenticated administrators — opens a page rendering that field, the browser executes the attacker's script in the site's origin context. The attacker can hijack sessions, perform forced actions through the WordPress REST API, or redirect visitors. See the plugin source reference and the patch changeset for the fixed implementation.

Detection Methods for CVE-2025-9044

Indicators of Compromise

Post metadata entries associated with Mapster WP Maps containing <script>, onerror=, onload=, or javascript: substrings
Unexpected outbound requests from administrator browser sessions shortly after viewing map-enabled pages
New or modified WordPress administrator accounts created by low-privilege users
Edits to posts containing map shortcodes made by contributor-level accounts

Detection Strategies

Query the wp_postmeta table for Mapster WP Maps keys and inspect values for HTML or JavaScript tokens
Review WordPress audit logs for contributor accounts editing posts that contain map fields
Enable Content Security Policy (CSP) reporting to catch inline script execution attempts on front-end pages
Monitor browser-side errors and CSP violations from administrator sessions as a secondary signal

Monitoring Recommendations

Alert on any file modifications under wp-content/plugins/mapster-wp-maps/ outside of planned update windows
Track creation and modification of posts by contributor-level users and queue them for moderator review
Capture WordPress REST API calls originating from administrator sessions that follow page views on content with embedded maps

How to Mitigate CVE-2025-9044

Immediate Actions Required

Update the Mapster WP Maps plugin to a version later than 1.20.0 that includes the vendor patch
Audit all existing posts and map entries for stored payloads and remove any injected markup
Restrict contributor-level access and review recent role assignments for unexpected users
Rotate administrator credentials and invalidate active sessions if exploitation is suspected

Patch Information

The vendor committed a fix in the plugin repository. Review the WordPress plugin changeset and install the latest release from the WordPress plugin directory. Verify the installed version through the WordPress admin dashboard after upgrade.

Workarounds

Temporarily deactivate the Mapster WP Maps plugin until the patched version is installed
Remove contributor and author permissions from untrusted accounts to reduce the exploitable population
Deploy a web application firewall (WAF) rule that blocks requests containing script tags or event-handler attributes targeting plugin field names
Enforce a strict Content Security Policy that disallows inline scripts on front-end pages

bash

# Configuration example: list installed version and update via WP-CLI
wp plugin get mapster-wp-maps --field=version
wp plugin update mapster-wp-maps
wp plugin status mapster-wp-maps