CVE-2025-9856
Unknown Unknown - Not Provided
Stored XSS in Popup Builder WordPress Plugin Allows Script Injection

Publication date: 2025-12-13

Last updated on: 2025-12-13

Assigner: Wordfence

Description
The Popup Builder – Create highly converting, mobile friendly marketing popups. plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'sg_popup' shortcode in all versions up to, and including, 4.4.1 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
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Meta Information
Published
2025-12-13
Last Modified
2025-12-13
Generated
2026-06-16
AI Q&A
2025-12-13
EPSS Evaluated
2026-06-15
NVD
CVE-2025-9856
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
wordpress popup_builder *
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-79 The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
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Detection Guidance

Detection of this vulnerability involves identifying if the Popup Builder WordPress plugin is installed and running a vulnerable version (up to and including 4.4.1). You can check the plugin version via WordPress admin dashboard or by inspecting the plugin files. Additionally, monitoring for suspicious stored scripts in pages using the 'sg_popup' shortcode may indicate exploitation attempts. Specific commands are not provided in the resources, but a common approach is to query the plugin version via WP-CLI with: `wp plugin list --format=json` and check for 'popup-builder' version <= 4.4.1. Also, scanning the database or page content for injected scripts in popup shortcode attributes could help detect exploitation. [1]

Executive Summary

This vulnerability is a Stored Cross-Site Scripting (XSS) issue in the Popup Builder WordPress plugin (up to version 4.4.1). It occurs because the plugin does not properly sanitize or escape user-supplied input in the 'sg_popup' shortcode attributes. Authenticated users with contributor-level access or higher can inject malicious scripts that will execute whenever any user views the affected page.

Impact Analysis

An attacker with contributor-level access or above can inject arbitrary scripts into pages, which will execute in the browsers of users who visit those pages. This can lead to theft of user data, session hijacking, defacement, or other malicious actions performed in the context of the affected website.

Mitigation Strategies

The immediate mitigation step is to update the Popup Builder plugin to version 4.4.2 or later, which includes security hardening to prevent this Stored Cross-Site Scripting vulnerability. The update improves input sanitization and output escaping, specifically sanitizing attribute keys and escaping attribute values in HTML output. Applying this update will prevent authenticated contributors from injecting malicious scripts via the 'sg_popup' shortcode. [1]

Compliance Impact

The provided resources and context do not contain information on how the CVE-2025-9856 vulnerability affects compliance with common standards and regulations such as GDPR or HIPAA.

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