CVE-2026-4388

Form Maker by 10Web <= 1.15.40 - Unauthenticated Stored Cross-Site Scripting via Matrix Field Text Box

2026-04-13 13:52
Naoya Takahashi (nakko)

Strategic Overview

Status
Patched in 1.15.41
Affected Plugin
Form Maker by 10Web – Mobile-Friendly Drag & Drop Contact Form Builder
Affected Version
<= 1.15.40
CVSS
7.2High
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2026-4388
View all Form Maker by 10Web – Mobile-Friendly Drag & Drop Contact Form Builder vulnerabilities

At a glance

CVE-2026-4388 is a high-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Form Maker by 10Web WordPress plugin, affecting versions <= 1.15.40. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 1.15.41; sites on affected versions should update now. Disclosed April 2026, reported by Naoya Takahashi (nakko).

Vulnerability Overview

The Form Maker by 10Web plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Matrix field (Text Box input type) in form submissions in all versions up to, and including, 1.15.40. This is due to insufficient input sanitization (`sanitize_text_field` strips tags but not quotes) and missing output escaping when rendering submission data in the admin Submissions view. This makes it possible for unauthenticated attackers to inject arbitrary JavaScript through a form submission that executes in the browser of an administrator who views the submission details.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Reaching this weakness in Form Maker by 10Web <= 1.15.40 takes no account at all. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Form Maker by 10Web the fix is 1.15.41: builds <= 1.15.40 are affected, anything from 1.15.41 onward is not.

Remediation

Update to version 1.15.41, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Form Maker by 10Web 1.15.41 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-4388https://www.wordfence.com/threat-intel/vulnerabilities/id/197449f5-9304-49df-9261-a354145fc00ehttps://nvd.nist.gov/vuln/detail/CVE-2026-4388

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C