What’s Vulnerable › Vulnerabilities

CVE-2026-100186: User Profile Builder <= 4.0.3 - Unauthenticated Stored Cross-Site Scripting via First Name Field

• Severity: high (CVSS 7.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-16 · updated 2026-10-16
• Weakness: CWE-79

Description

The User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via First Name Field in all versions up to, and including, 4.0.3 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. This vulnerability is only exploitable when the Email Confirmation feature is enabled in Profile Builder.

Affected products

• cozmoslabs User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor: through 4.0.3

References

• https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/features/email-confirmation/class-email-confirmation.php#L100
• https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/features/email-confirmation/class-email-confirmation.php#L99
• https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/features/email-confirmation/email-confirmation.php#L470
• https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/front-end/default-fields/first-name/first-name.php#L56
• https://plugins.trac.wordpress.org/changeset/3741133/profile-builder
• https://plugins.trac.wordpress.org/changeset/3741133/profile-builder/trunk/features/email-confirmation/class-email-confirmation.php
• https://www.wordfence.com/threat-intel/vulnerabilities/id/f3f2ecdb-bbd0-4834-b731-88724ca0dfd7?source=cve

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