CVE-2025-31890: Simple Map No Api Stored XSS Vulnerability

CVE-2025-31890 Overview

CVE-2025-31890 is a stored cross-site scripting (XSS) vulnerability in the Mashi Simple Map No Api WordPress plugin (simple-map-no-api). The flaw affects all plugin versions up to and including 1.9. Attackers with low-privileged authenticated access can inject malicious scripts that persist in the database and execute in the browsers of users viewing affected pages. The vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation.

Critical Impact

Authenticated attackers can inject persistent JavaScript payloads that execute against site visitors and administrators, enabling session theft, credential harvesting, and administrative account compromise through scope-changing script execution.

Affected Products

• Mashi Simple Map No Api (simple-map-no-api) plugin for WordPress
• All versions from initial release through version 1.9
• WordPress sites with the vulnerable plugin activated

Discovery Timeline

• 2025-04-01 - CVE-2025-31890 published to the National Vulnerability Database
• 2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-31890

Vulnerability Analysis

The Simple Map No Api plugin fails to properly neutralize user-supplied input before rendering it within generated web pages. Attackers with contributor-level access or higher can submit crafted input containing HTML or JavaScript payloads. The plugin stores this input without sanitization and later renders it into the DOM without output encoding.

Because the payload is stored server-side, it executes automatically whenever a user loads an affected page. The scope change component of this vulnerability indicates that injected scripts can influence resources beyond the vulnerable component, such as the administrative dashboard. User interaction is required for exploitation, typically an administrator viewing content that contains the injected payload.

Root Cause

The root cause is missing input validation and output encoding when the plugin processes map configuration parameters or associated user-controllable fields. WordPress provides functions such as esc_html(), esc_attr(), and wp_kses() for context-appropriate output escaping, but the vulnerable plugin does not consistently apply these to attacker-controlled data before rendering.

Attack Vector

Exploitation requires network access to the WordPress site and low-privileged authenticated access. An attacker submits crafted input through a plugin field that accepts map-related parameters. The malicious payload persists in the WordPress database. When any authenticated user or site visitor loads a page rendering the stored value, the browser parses and executes the injected script in the context of the target site.

Refer to the Patchstack Vulnerability Advisory for additional technical details about the injection point.

Detection Methods for CVE-2025-31890

Indicators of Compromise

• Unexpected <script> tags, event handlers such as onerror or onload, or javascript: URIs stored in WordPress post metadata or plugin option tables.
• Outbound HTTP requests from browsers rendering site pages to unfamiliar third-party domains referencing session cookies.
• New WordPress administrator accounts or unauthorized modifications to user roles following user interaction with plugin-rendered content.

Detection Strategies

• Audit database tables (wp_options, wp_postmeta) for stored HTML or JavaScript content associated with the simple-map-no-api plugin.
• Deploy a Web Application Firewall (WAF) with rules that inspect POST parameters targeting plugin endpoints for XSS payload signatures.
• Enable Content Security Policy (CSP) reporting to identify script execution originating from unexpected inline sources.

Monitoring Recommendations

• Log and review all contributor and author level submissions to the WordPress site, correlating with subsequent administrator page views.
• Monitor WordPress plugin activity logs for changes to Simple Map No Api configuration and shortcodes.
• Alert on anomalous session activity such as unexpected privilege elevation or password resets initiated from administrator sessions.

How to Mitigate CVE-2025-31890

Immediate Actions Required

• Deactivate and remove the Simple Map No Api plugin from all WordPress installations until a patched version becomes available.
• Audit all user submissions and plugin-managed content for injected scripts and remove malicious entries from the database.
• Rotate credentials for any WordPress administrators who accessed pages containing potentially malicious plugin output.

Patch Information

At the time of publication, no patched version is listed in the advisory. Consult the Patchstack Vulnerability Advisory for the latest remediation guidance and monitor the WordPress plugin repository for updates beyond version 1.9.

Workarounds

• Restrict contributor and author account creation and enforce strong authentication for all WordPress users capable of submitting content.
• Implement a strict Content Security Policy that disallows inline scripts and untrusted script sources to limit the impact of injected payloads.
• Deploy a WAF ruleset that filters XSS payloads targeting plugin request parameters until the plugin is removed or updated.

# Example Content Security Policy header for Apache
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'"