Description

Subscriber Privilege Escalation in Fluent Forms Pro Add On Pack <= 6.2.12 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.5",
  "pubDate": "2026-08-31T21:17:50.420Z",
  "pubdate": "2026-08-31T21:17:50.420Z",
  "executiveSummary": "The Fluent Forms Pro Add On Pack, specifically versions 6.2.12 and below, contains a critical vulnerability related to improper privilege management. This security flaw allows an authenticated user with minimal privileges, such as a Subscriber, to perform unauthorized actions and escalate their privileges within the WordPress environment.\nThe vulnerability type is classified as an Insecure Privilege Assignment or Privilege Escalation. By leveraging this flaw, an attacker can bypass intended access controls to modify site settings or perform administrative functions that should be restricted to users with higher authorization levels.\nThis vulnerability poses a significant risk to the integrity and security of the WordPress installation. Successful exploitation could lead to full site compromise, as an attacker with escalated privileges can install malicious plugins, modify user databases, or inject arbitrary code. The exploitation requires the attacker to hold at least a Subscriber-level account, meaning the entry barrier is relatively low in environments where user registration is enabled. No specialized network access is required, as the vulnerability is triggered via standard HTTP requests processed by the application’s backend controllers.\nOrganizations using the affected software are strongly advised to restrict user registration and prioritize the application of vendor-provided security patches to remediate the underlying access control logic error.",
  "technicalDetails": "The vulnerability resides within the request handling and authorization logic of the Fluent Forms Pro Add On Pack. Specifically, the component responsible for processing form-related configuration updates or administrative actions fails to adequately validate the authorization level of the requesting user. In WordPress, plugins are expected to utilize current_user_can() checks to ensure that a user possesses the 'manage_options' or equivalent capability before executing sensitive functions. In the affected versions, these checks are either absent, improperly implemented, or bypassed during the lifecycle of a specific request handler.\nThe root cause is an improper authorization check in the plugin’s backend API controllers. When a user sends a request to the vulnerable endpoint, the plugin logic fails to verify if the session associated with the request possesses the required administrative capabilities. Consequently, the application assumes the request is authorized by an administrator, allowing the user to bypass the standard WordPress capability checks.\nThe attack flow proceeds as follows: First, an attacker authenticates as a low-privileged user (Subscriber). Second, the attacker identifies the specific API endpoint or action hook utilized by the Fluent Forms Pro Add On Pack for administrative modifications. Third, the attacker crafts a POST request containing the necessary parameters to invoke the restricted function. Because the server-side code fails to validate the user's role before processing the data, the plugin executes the requested operation with elevated permissions.\nBecause this is a server-side logic flaw, the payload behavior manifests as an unauthorized state change within the WordPress database. An attacker might exploit this to alter form processing logic, modify webhook endpoints, or potentially inject serialized data if the plugin handles form configurations through insecure deserialization patterns. The post-exploitation impact includes the potential for persistent administrative access, as the attacker can manipulate the user management functions or exfiltrate sensitive configuration data stored within the Fluent Forms tables.\nThe affected versions are strictly identified as Fluent Forms Pro Add On Pack <= 6.2.12. This vulnerability is not dependent on specific network configurations but is rather inherent to the plugin's internal request processing architecture. Remediation requires ensuring that every sensitive administrative function within the plugin's codebase is wrapped in a secure capability check to enforce the Principle of Least Privilege."
}