CVE-2025-14028 Overview
CVE-2025-14028 is a Stored Cross-Site Scripting (XSS) vulnerability in the Contact Us Simple Form plugin for WordPress, affecting all versions up to and including 1.0. The flaw stems from insufficient input sanitization and output escaping on user-supplied attributes within the plugin's admin settings. Authenticated attackers with administrator-level access can inject arbitrary web scripts that execute when any user accesses an affected page. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation).
Critical Impact
Authenticated administrators can persist malicious JavaScript in plugin settings, enabling session hijacking, credential theft, and unauthorized actions against any user who loads the injected page.
Affected Products
- Contact Us Simple Form plugin for WordPress, all versions up to and including 1.0
- WordPress sites with the plugin installed and active
- Any administrator account on affected WordPress installations
Discovery Timeline
- 2026-01-07 - CVE-2025-14028 published to NVD
- 2026-04-15 - Last updated in NVD database
Technical Details for CVE-2025-14028
Vulnerability Analysis
The vulnerability resides in the Contact Us Simple Form plugin's admin settings handler. When an authenticated administrator submits configuration values, the plugin stores those inputs without applying adequate sanitization functions such as sanitize_text_field() or wp_kses(). The stored values are subsequently rendered into HTML output without proper escaping through esc_attr() or esc_html(). Researchers identified the unsafe handling at lines 223 and 239 of contact-us-simple-form.php, where attribute values are emitted directly into the page markup.
Because the payload is persisted in the WordPress database, every visitor or administrator who loads the affected page triggers script execution within their browser session. The attack requires high privileges, which limits practical exploitation to scenarios involving compromised admin credentials, rogue administrators, or multi-administrator environments where one admin targets others.
Root Cause
The root cause is missing input validation and missing output encoding on user-supplied attributes processed by the plugin's settings page. The plugin trusts administrator input implicitly and writes raw values into HTML attribute contexts. WordPress provides built-in escaping APIs that the plugin code does not invoke at the vulnerable code paths.
Attack Vector
An attacker with administrator privileges navigates to the Contact Us Simple Form settings interface and supplies a malicious payload, such as JavaScript embedded inside an attribute value or <script> tag, into one of the configurable fields. The plugin saves the unsanitized value to the wp_options table. When the affected page renders, the browser parses the payload as executable script, allowing the attacker to perform actions in the context of any viewing user, including stealing cookies, hijacking sessions, or pivoting to additional accounts.
For technical details, see the Wordfence Vulnerability Analysis and the WordPress Plugin Source Code Line 223 and Line 239 references.
Detection Methods for CVE-2025-14028
Indicators of Compromise
- Unexpected <script> tags, javascript: URIs, or event handler attributes (onerror, onload) stored in the wp_options table under Contact Us Simple Form settings keys
- Outbound requests from visitor browsers to unfamiliar domains coinciding with views of pages rendering the plugin output
- Unauthorized administrator logins or session token reuse following access to pages embedding the plugin
Detection Strategies
- Audit the WordPress database for HTML or JavaScript artifacts inside Contact Us Simple Form configuration values
- Review WordPress audit logs for update_option events targeting the plugin's settings by administrator accounts
- Inspect rendered HTML on pages where the plugin is used for unescaped attribute values originating from plugin settings
Monitoring Recommendations
- Enable a WordPress activity logging plugin to capture administrator setting changes with user attribution and timestamps
- Deploy a web application firewall (WAF) with XSS rule sets to identify and block payloads delivered to plugin admin endpoints
- Monitor browser-side Content Security Policy (CSP) violation reports to surface unexpected inline script execution
How to Mitigate CVE-2025-14028
Immediate Actions Required
- Deactivate and remove the Contact Us Simple Form plugin until a patched release is available, as all versions through 1.0 are affected
- Audit existing plugin settings in the database and remove any values containing HTML or JavaScript content
- Rotate administrator credentials and active sessions if unauthorized setting modifications are identified
Patch Information
At the time of NVD publication, no patched version of the Contact Us Simple Form plugin has been identified in the available references. Monitor the WordPress plugin repository and the Wordfence advisory for fix availability.
Workarounds
- Restrict administrator account assignments and enforce multi-factor authentication on all admin users to reduce the attacker pool
- Implement a strict Content Security Policy that blocks inline scripts and unapproved external script sources
- Apply WAF rules that filter HTML tags and JavaScript event handlers in POST requests targeting the plugin's settings endpoint
# Configuration example: disable the plugin via WP-CLI until a patch is released
wp plugin deactivate contact-us-simple-form
wp plugin delete contact-us-simple-form
# Verify no residual settings remain in the options table
wp option list --search='contact_us_simple_form*'
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
