Ninja Forms Plugin up to 3.15.5 on WordPress Input Sanitization querystring cross site scripting

Summaryinfo

A vulnerability was found in Ninja Forms Plugin up to 3.15.5. It has been declared as problematic. This issue affects some unknown processing of the component Input Sanitization. Such manipulation of the argument querystring leads to cross site scripting. This vulnerability is traded as CVE-2026-100151. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Ninja Forms Plugin up to 3.15.5. Affected by this issue is some unknown processing of the component Input Sanitization. The manipulation of the argument querystring with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to 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. Impacted is integrity. CVE summarizes:

The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for WordPress is vulnerable to Reflected DOM-Based Cross-Site Scripting via 'querystring:<key>' URL Parameter in all versions up to, and including, 3.15.5 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. This bypass is triggered when an attacker supplies a matching field:&lt;key&gt; URL parameter that causes the server to fully resolve the {field:*} placeholder, forcing the client-side else-branch to abandon the server-sanitized value and reconstruct field content from the raw query string.

The advisory is available at wordfence.com. This vulnerability is handled as CVE-2026-100151 since 09/25/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• WordPress Plugin

Name

• Ninja Forms Plugin

Version

• 3.15.0
• 3.15.1
• 3.15.2
• 3.15.3
• 3.15.4
• 3.15.5

CPE 2.3info

• 🔒
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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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