Description

Authorization Bypass Through User-Controlled Key vulnerability in NOUS Ouvert Utile et Simple Event post event-post allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects Event post: from n/a through 6.1.1.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.5",
  "pubDate": "2026-10-12T08:17:18.317Z",
  "pubdate": "2026-10-12T08:17:18.317Z",
  "executiveSummary": "The Event post plugin for WordPress, developed by NOUS Ouvert Utile et Simple, is susceptible to an Authorization Bypass Through User-Controlled Key vulnerability.\nThis security flaw stems from an incorrectly configured access control mechanism within the application's security architecture.\nThe vulnerability allows unauthenticated or unauthorized remote attackers to bypass intended security restrictions and potentially interact with restricted event-post functionalities.\nBy manipulating specific keys or parameters, an attacker can elevate their access level to perform actions that should be gated by more robust authorization checks.\nThe impact is categorized as high, as it compromises the integrity and confidentiality of the event management system, potentially allowing unauthorized data modification or administrative actions depending on the specific endpoint exposed.\nAffected systems include versions of Event post from n/a through 6.1.1.\nExploitation does not necessarily require high-level credentials, as the flaw lies in the backend validation logic of the user-controlled key.",
  "technicalDetails": "The root cause of this vulnerability is improper server-side validation of user-supplied keys utilized within the Event post plugin's authorization logic.\nSpecifically, the application fails to verify whether a user possesses the appropriate security level before processing requests that involve user-controlled identifiers.\nThe vulnerability occurs within the request handling flow where the plugin determines access rights based on keys provided via the HTTP request.\nWhen a user submits a request containing a specific, user-controlled key, the application's internal access control handler incorrectly validates this input against existing security levels.\nBecause the key is attacker-controllable and the validation check is insufficient, the system erroneously grants the requested access level to the user.\nThe attack flow proceeds as follows: First, an attacker identifies the target endpoint responsible for event-post functionality within the WordPress environment. Second, the attacker performs reconnaissance to determine the expected structure of the user-controlled key. Third, the attacker crafts a malicious request by injecting or manipulating this key to correspond with a higher privilege security level. Fourth, upon the server receiving the request, the flawed access control component fails to enforce authentication or authorization constraints. Fifth, the application processes the request as if it originated from an authorized user, thereby executing the intended action.\nThis vulnerability highlights a critical failure in the Principle of Least Privilege, as the application relies on client-side or easily manipulated parameters to enforce server-side security boundaries.\nThe scope of impact includes unauthorized access to restricted event data, potential unauthorized modification of event configurations, and potential further escalation if the affected function interacts with other vulnerable system components.\nSince this is an authorization bypass, it essentially renders the plugin's native security levels ineffective against any actor who identifies the key generation logic or successfully guesses a valid key string.\nThe vulnerability is present in versions up to 6.1.1, affecting the core operational logic of the plugin's access control layer."
}