WordPress security changelog
HIGH CVE-2026-81660 Deferred

Groundhogg web forms permit unauthenticated stored XSS against administrators

Groundhogg before 4.5.13 does not validate or escape values submitted through some optional web form fields before storing and rendering them in an administrative area. An unauthenticated visitor can submit script content that executes when a high-privilege user views the affected data.

CVE / CNA score 8.8 CVSS 3.1 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD score Pending NVD has not published its own CVSS assessment.
Component
Groundhogg — CRM, Newsletters, and Marketing Automation
Plugin slug
groundhogg-crm-newsletters-and-marketing-automation
Affected
< 4.5.13
Safe version
4.5.13
Published
Aug 30, 2026
Weakness
CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

This CVE was published Aug 30, 2026 and is one of 3 known issues for this plugin.

Update, patch or deactivate.

Update Groundhogg to 4.5.13 or later, review stored form submissions for injected markup, and inspect privileged-session activity if administrators viewed untrusted submissions.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Technical description

The Groundhogg — CRM, Newsletters, and Marketing Automation WordPress plugin before 4.5.13 does not validate or escape values submitted to some optional web form fields before storing them and outputting them back in an administrative area, allowing unauthenticated users to perform Stored Cross-Site Scripting attacks against high privilege users.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Primary and upstream sources