techjewel Fluent Forms Plugin up to 6.1.21 on WordPress Query Parameter SubmissionPolicy form_id authorization

Summaryinfo

A vulnerability labeled as critical has been found in techjewel Fluent Forms Plugin up to 6.1.21 on WordPress. Affected by this vulnerability is the function SubmissionPolicy of the component Query Parameter Handler. Executing a manipulation of the argument form_id can lead to authorization. The identification of this vulnerability is CVE-2026-5396. The attack may be launched remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in techjewel Fluent Forms Plugin up to 6.1.21 on WordPress. It has been declared as critical. This vulnerability affects the function SubmissionPolicy of the component Query Parameter Handler. The manipulation of the argument form_id with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The Fluent Forms plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in all versions up to, and including, 6.1.21. This is due to the SubmissionPolicy class authorizing submission-level actions (read, modify, delete, add notes) based on a user-supplied `form_id` query parameter. This makes it possible for authenticated attackers, with Fluent Forms Manager access restricted to specific forms, to read, modify status, add notes to, and permanently delete form submissions belonging to any other form by spoofing the form_id parameter to a form they are authorized for.

The weakness was shared by Sander Horsman. The advisory is available at wordfence.com. This vulnerability was named CVE-2026-5396 since 04/02/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit.

Upgrading to version 6.1.21 eliminates this vulnerability.

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Productinfo

Type

• WordPress Plugin

Vendor

• techjewel

Name

• Fluent Forms Plugin

Version

• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21

CPE 2.3info

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CPE 2.2info

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