CVE-2026-35476: InvenTree Auth Bypass Vulnerability

CVE-2026-35476 Overview

CVE-2026-35476 is a privilege escalation vulnerability affecting InvenTree, an Open Source Inventory Management System. Prior to versions 1.2.7 and 1.3.0, a non-staff authenticated user can elevate their account to a staff level via a POST request against their user account endpoint. The write permissions on the API endpoint are improperly configured, allowing any user to change their staff status. This vulnerability is classified under CWE-285 (Improper Authorization).

Critical Impact

Authenticated users can escalate privileges to staff level by exploiting misconfigured API write permissions, potentially gaining administrative control over the inventory management system.

Affected Products

• InvenTree versions prior to 1.2.7
• InvenTree versions prior to 1.3.0
• Self-hosted and deployed InvenTree instances running vulnerable versions

Discovery Timeline

• 2026-04-08 - CVE-2026-35476 published to NVD
• 2026-04-08 - Last updated in NVD database

Technical Details for CVE-2026-35476

Vulnerability Analysis

This privilege escalation vulnerability stems from improperly configured API endpoint permissions within InvenTree's user management functionality. The vulnerability allows any authenticated user—regardless of their current privilege level—to modify their own account attributes, including the critical is_staff flag that determines administrative access.

When a legitimate user authenticates to the InvenTree system, they gain access to API endpoints that manage user profile data. Due to the authorization misconfiguration, the API endpoint responsible for user account modifications fails to properly restrict which fields an authenticated user can update. This allows a low-privileged user to craft a malicious POST request that sets their is_staff attribute to true, effectively granting themselves staff-level privileges.

The impact of successful exploitation is significant—staff accounts in InvenTree typically have elevated permissions including the ability to manage inventory, view sensitive data, modify system configurations, and potentially access other user accounts.

Root Cause

The root cause of CVE-2026-35476 is improper access control implementation (CWE-285) on the user account API endpoint. The endpoint accepts write operations on sensitive user attributes without verifying whether the requesting user has sufficient privileges to modify those specific fields. The API should restrict modification of privilege-related fields to administrators only, but the flawed implementation allows any authenticated user to update these fields on their own account.

Attack Vector

The attack vector for this vulnerability is network-based and requires authentication. An attacker must first have a valid, authenticated user account on the InvenTree instance. Once authenticated, the attacker can send a crafted POST request to their user account endpoint, modifying the staff status flag. The attack does not require any user interaction and can be executed with low complexity.

The exploitation flow involves:

1. Authenticating to InvenTree with a standard (non-staff) user account
2. Sending a POST request to the user account API endpoint
3. Including the staff status modification in the request body
4. The server processes the request without proper authorization checks
5. The attacker's account is elevated to staff level

For detailed technical information, refer to the GitHub Security Advisory GHSA-r8q5-3595-3jh2.

Detection Methods for CVE-2026-35476

Indicators of Compromise

• Unexpected changes to user account privilege levels, particularly non-staff users gaining staff status
• API logs showing POST requests to user account endpoints containing staff status modifications
• Audit logs revealing users performing administrative actions who were not previously authorized as staff
• Multiple rapid privilege changes on user accounts in a short timeframe

Detection Strategies

• Implement API request logging and monitor for POST requests to user account endpoints that modify privilege-related fields
• Create alerts for any changes to the is_staff attribute on user accounts, especially self-modifications
• Review authentication logs for users who suddenly gain access to administrative functionality
• Deploy web application firewalls (WAF) with rules to detect privilege escalation patterns in API requests

Monitoring Recommendations

• Enable comprehensive audit logging for all user account modifications within InvenTree
• Set up automated alerts for privilege escalation events where non-administrative users gain staff status
• Monitor API traffic patterns for anomalous POST requests to user management endpoints
• Regularly review user privilege assignments and compare against expected baseline configurations

How to Mitigate CVE-2026-35476

Immediate Actions Required

• Upgrade InvenTree to version 1.2.7 or 1.3.0 or later immediately
• Audit all user accounts to identify any unauthorized privilege escalations
• Review API access logs for evidence of exploitation attempts
• Revoke staff privileges from any accounts that were improperly elevated
• Consider temporarily restricting API access until patches are applied

Patch Information

The InvenTree development team has addressed this vulnerability in versions 1.2.7 and 1.3.0. Organizations should upgrade to these patched versions as soon as possible. The fix implements proper authorization checks on the user account API endpoint, ensuring that only administrators can modify privilege-related fields.

For more information, consult the GitHub Security Advisory GHSA-r8q5-3595-3jh2 and the InvenTree Threat Model Documentation.

Workarounds

• If immediate patching is not possible, implement network-level restrictions to limit API access to trusted IP ranges
• Deploy a reverse proxy or WAF to filter API requests attempting to modify staff status fields
• Disable direct API access and route all user management through administrative interfaces with proper access controls
• Consider placing InvenTree behind a VPN to limit exposure while awaiting patch deployment

# Example: Restrict API access via nginx configuration
location /api/user/ {
    # Restrict access to trusted networks only
    allow 10.0.0.0/8;
    allow 192.168.0.0/16;
    deny all;
    
    # Additional rate limiting
    limit_req zone=api_limit burst=5 nodelay;
    
    proxy_pass http://inventree_backend;
}