CVE-2026-11880

Fluent Forms <= 6.2.0 - Insecure Direct Object Reference to Authenticated (Subscriber+) Subscription Cancellation

2026-08-10 00:00
Pedro Pinho

Strategic Overview

Status
Patched in 6.2.1
Affected Plugin
Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder
Affected Version
<= 6.2.0
CVSS
4.3Medium
Weakness type
CWE-639 · Authorization Bypass Through User-Controlled Key
CVE
CVE-2026-11880
View all Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder vulnerabilities

At a glance

CVE-2026-11880 is a medium-severity Authorization Bypass Through User-Controlled Key vulnerability in the Fluent Forms WordPress plugin, affecting versions <= 6.2.0. It carries a CVSS score of 4.3 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 6.2.1; sites on affected versions should update now. Disclosed August 2026, reported by Pedro Pinho.

Vulnerability Overview

The Fluent Forms plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to, and including, 6.2.0. This is due to missing ownership validation on the subscription_id parameter in the cancel_subscription AJAX route, allowing any authenticated user to cancel subscriptions tied to forms they do not manage. This makes it possible for authenticated attackers, with subscriber-level access and above, to cancel arbitrary payment subscriptions belonging to other users by supplying a foreign subscription_id.

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 interaction from a victim user.

CWE-639: Authorization Bypass Through User-Controlled Key

Reaching this weakness in Fluent Forms <= 6.2.0 takes an account at Subscriber level or above. Authorization bypass through a user-controlled key, often called insecure direct object reference, means the application looks up a record by an identifier from the request without checking that the caller owns it.

Changing a number in the request is enough to read or modify other users' records, which on commerce and membership sites means customer data. For Fluent Forms the fix is 6.2.1: builds <= 6.2.0 are affected, anything from 6.2.1 onward is not.

Remediation

Update to version 6.2.1, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Fluent Forms 6.2.1 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-11880https://www.wordfence.com/threat-intel/vulnerabilities/id/17621978-cff5-4e63-bf6e-f1349da74730https://nvd.nist.gov/vuln/detail/CVE-2026-11880

Related records

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