CVE-2026-18548
Deferred Deferred - Pending Action

Stored XSS in Groundhogg WordPress Plugin

Publication date: 2026-10-15

Last updated on: 2026-10-15

Assigner: Wordfence

Description
The Groundhogg — CRM, Newsletters, and Marketing Automation plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'ref' parameter in all versions up to, and including, 4.5.14 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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Meta Information

Published
2026-10-15
Last Modified
2026-10-15
Generated
2026-10-19
AI Q&A
2026-10-15
EPSS Evaluated
2026-10-18
NVD
CVE-2026-18548
EUVD
EUVD-2026-101843

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
trainingbusinesspros Groundhogg — CRM, Newsletters, and Marketing Automation 0

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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Executive Summary

This vulnerability is a Stored Cross-Site Scripting (XSS) issue in the Groundhogg WordPress plugin. It occurs due to insufficient input sanitization and output escaping in the 'ref' parameter, allowing unauthenticated attackers to inject malicious scripts into web pages. These scripts execute when users access the compromised pages.

Detection Guidance

Check WordPress installations for the Groundhogg plugin versions up to 4.5.14. Inspect server logs for unusual script injections in the 'ref' parameter. Use security plugins like Wordfence to scan for stored XSS patterns.

Impact Analysis

Unauthenticated attackers could inject malicious scripts into your WordPress site, potentially stealing user data, session cookies, or performing actions on behalf of users. Visitors to your site may have their accounts compromised or be redirected to malicious websites.

Compliance Impact

This vulnerability could lead to unauthorized access to user data, violating GDPR's data protection requirements and HIPAA's safeguards for protected health information. Non-compliance may result in legal penalties, reputational damage, and loss of trust.

Mitigation Strategies

Update the Groundhogg plugin to the latest version beyond 4.5.14. If an update is unavailable, disable the plugin temporarily. Implement web application firewalls to block XSS attempts.

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