High severity · published Oct 16, 2026
CVE-2026-100186
User Profile Builder <= 4.0.3 - Unauthenticated Stored Cross-Site Scripting via First Name Field
7.2
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UP
User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor · cozmoslabs
through 4.0.3 · source: vendor
Affected product
UP
User Profile Builder – Beautiful User Registration Forms, User Profiles & User Role Editor
cozmoslabs
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-100186
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-100186
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/features/email-confirmation/class-email-confirmation.php#L100
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/features/email-confirmation/class-email-confirmation.php#L99
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/features/email-confirmation/email-confirmation.php#L470
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/profile-builder/tags/4.0.3/front-end/default-fields/first-name/first-name.php#L56
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3741133/profile-builder
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3741133/profile-builder/trunk/features/email-confirmation/class-email-confirmation.php
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