Description

A vulnerability was found in FluentCMS up to 0.0.5. This affects the function GetAccessible of the file src/Backend/FluentCMS.Services/Permissions/PermissionManager.cs. Performing a manipulation results in missing authorization. It is possible to initiate the attack remotely. The exploit has been made public and could be used. The project was informed of the problem early through an issue report but has not responded yet.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.7",
  "pubDate": "2026-09-07T05:16:55.210Z",
  "pubdate": "2026-09-07T05:16:55.210Z",
  "executiveSummary": "A critical authorization vulnerability has been identified in FluentCMS versions up to 0.0.5, specifically residing within the permission management logic. The vulnerability manifests as a missing authorization check, allowing unauthorized actors to potentially access restricted resources or perform actions reserved for higher-privileged accounts.\nThis flaw is categorized as a Missing Authorization vulnerability, which can be exploited remotely over a network without requiring prior authentication. The security implications are significant, as an attacker can bypass defined access control mechanisms to gain unauthorized access to sensitive data or perform administrative tasks within the application context.\nThe vulnerability is currently unpatched, and public exploit material exists, increasing the risk of active exploitation. Organizations utilizing affected versions of FluentCMS are at high risk of unauthorized data access and integrity compromise. The attack vector is remote, necessitating immediate attention to secure the environment against potential exploitation attempts.",
  "technicalDetails": "The vulnerability is located in the src/Backend/FluentCMS.Services/Permissions/PermissionManager.cs file, specifically within the GetAccessible function. The root cause of this security defect is the failure to properly enforce authorization checks during the evaluation of resource accessibility requests.\nThe GetAccessible function is responsible for determining whether a user or process possesses the necessary permissions to access specific resources within the FluentCMS architecture. Due to the missing authorization logic, the function fails to validate the requester's identity or role-based access control (RBAC) credentials against the target resource's security policy. Consequently, the function proceeds to grant access based on malformed or malicious inputs rather than enforcing established security constraints.\nThe attack flow for this vulnerability involves an attacker crafting a request directed at the affected endpoint. Since the function lacks a robust validation mechanism, the attacker can manipulate parameters to trick the PermissionManager into granting unauthorized access. This can be performed remotely, requiring no interaction with an authenticated session. By interacting directly with the service, an attacker can bypass the intended authorization perimeter.\nThe exploitation process typically involves identifying the specific resource paths governed by the GetAccessible function and submitting requests that omit or forge authorization headers/tokens. Because the function does not verify if the current context has the appropriate permissions, it returns a successful result, exposing protected backend resources to the attacker. This enables horizontal or vertical privilege escalation, where the attacker can view or manipulate data they should not have access to.\nThe impact of a successful exploitation is severe. Post-exploitation, an attacker can access administrative APIs, retrieve sensitive database information, or execute unauthorized operations. Given the public availability of exploit code, the barrier to entry for malicious actors is extremely low. The vulnerability affects the core permission management component, meaning that if left unaddressed, the entire authorization infrastructure of the application remains compromised.\nThis vulnerability is particularly dangerous because it occurs at the service layer, effectively bypassing the security controls that would normally protect the backend application logic. The lack of proper authorization checks in src/Backend/FluentCMS.Services/Permissions/PermissionManager.cs undermines the confidentiality and integrity of the entire FluentCMS ecosystem."
}