Description

Unauthenticated Broken Access Control in Simple Membership <= 4.7.8 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.5",
  "pubDate": "2026-08-06T15:17:24.307Z",
  "pubdate": "2026-08-06T15:17:24.307Z",
  "executiveSummary": "An unauthenticated broken access control vulnerability exists in the Simple Membership plugin for versions 4.7.8 and below. This security flaw allows unauthenticated remote attackers to bypass authorization mechanisms and interact with restricted functionalities or data intended solely for privileged users.\nThe root of the issue lies in the inadequate validation of user privileges and session states within the plugin's access control enforcement logic, leaving sensitive endpoints exposed across the network.\nSuccessful exploitation of this vulnerability does not require any user interaction, administrative privileges, or prior authentication, significantly lowering the attack complexity.\nThe risk implications include unauthorized access to protected resources, potential data exposure, and unauthorized manipulation of state within the context of the affected WordPress application.\nMitigation requires upgrading the Simple Membership plugin to a version subsequent to 4.7.8 where the access control checks have been properly implemented and enforced.",
  "technicalDetails": "The vulnerability is classified under broken access control, specifically stemming from missing authorization checks on sensitive application functions within the Simple Membership plugin.\nThe affected product is the Simple Membership plugin, encompassing all versions up to and including version 4.7.8.\nThe vulnerable component handles requests that dictate access to protected content or administrative actions without properly verifying whether the incoming HTTP request originates from an authenticated entity possessing the requisite role or capability.\nNetwork exposure is fully remote, as the vulnerable endpoints are accessible over standard HTTP/HTTPS protocols exposed by the underlying WordPress installation hosting the plugin.\nAuthentication requirements are entirely absent, allowing unauthenticated threat actors to interact directly with the affected functions. Privilege requirements are similarly nonexistent prior to exploitation, as the flaw bypasses authorization layers altogether.\nThe attack flow proceeds as follows: First, an attacker identifies the exposed functional endpoints or URL routes managed by the Simple Membership plugin that lack proper access control validation. Second, the attacker crafts an arbitrary HTTP request targeting these restricted resources without supplying valid session cookies, authentication tokens, or authorization headers. Third, the plugin processes the incoming request and executes the underlying business logic or serves the restricted resource due to the complete absence of capability checks. Finally, the attacker achieves unauthorized access to restricted data or functionality.\nThe post-exploitation impact depends on the specific capabilities exposed by the unauthenticated endpoints, potentially leading to unauthorized data disclosure, privilege escalation, or unauthorized modification of membership records within the application database."
}