CVE-2026-3263: ASP.NET Core Auth Bypass Vulnerability

CVE-2026-3263 Overview

A vulnerability was discovered in go2ismail Asp.Net-Core-Inventory-Order-Management-System up to version 9.20250118. This security flaw affects the Security API component at the /api/Security/ endpoint, allowing improper authorization that can lead to unauthorized access to security-related functionality. The vulnerability can be exploited remotely over the network by authenticated users with low privileges.

Critical Impact

This Insecure Direct Object Reference (IDOR) vulnerability in the Security API can potentially lead to full system compromise by allowing attackers to manipulate authorization controls and access restricted resources.

Affected Products

• go2ismail Asp.Net-Core-Inventory-Order-Management-System up to version 9.20250118

Discovery Timeline

• 2026-02-26 - CVE-2026-3263 published to NVD
• 2026-02-26 - Last updated in NVD database

Technical Details for CVE-2026-3263

Vulnerability Analysis

This vulnerability is classified under CWE-266 (Incorrect Privilege Assignment), which occurs when a product does not properly assign or verify privileges during object access operations. The Security API endpoint /api/Security/ fails to properly validate whether the authenticated user has the necessary privileges to perform requested operations.

The flaw allows authenticated users with low-level privileges to access or manipulate security-related resources that should be restricted to higher-privileged accounts. This represents a classic Insecure Direct Object Reference (IDOR) pattern where authorization checks are either missing or improperly implemented in the API layer.

Root Cause

The root cause of this vulnerability stems from improper authorization validation in the Security API component. The application fails to verify that the authenticated user has appropriate privileges before processing requests to the /api/Security/ endpoint. This allows attackers to bypass intended access controls by directly referencing security objects without proper privilege verification.

Attack Vector

The attack can be performed remotely over the network by any authenticated user. The attacker needs valid credentials with low-level privileges to access the system. Once authenticated, the attacker can directly access the /api/Security/ endpoint and manipulate or view security-related resources that should be restricted to administrators or users with elevated privileges.

The vulnerability requires no user interaction beyond the initial authentication. Due to the nature of IDOR vulnerabilities, exploitation typically involves manipulating object identifiers or parameters in API requests to access resources belonging to other users or higher-privileged accounts.

For detailed technical information about the exploitation methodology, refer to the GitHub Security Advisory.

Detection Methods for CVE-2026-3263

Indicators of Compromise

• Unusual access patterns to /api/Security/ endpoint from low-privileged user accounts
• Audit logs showing security configuration changes made by non-administrative users
• API requests containing manipulated object identifiers targeting security resources
• Multiple rapid sequential requests to the Security API from a single session

Detection Strategies

• Implement logging and monitoring for all requests to the /api/Security/ endpoint
• Deploy Web Application Firewall (WAF) rules to detect IDOR patterns in API requests
• Configure alerting for privilege escalation attempts or unauthorized access to administrative functions
• Review access logs for anomalous behavior from authenticated users accessing security endpoints

Monitoring Recommendations

• Enable detailed audit logging for all Security API operations
• Monitor for failed authorization attempts followed by successful unauthorized access
• Implement real-time alerting for any modifications to security configurations by non-admin users
• Correlate authentication events with subsequent Security API access patterns

How to Mitigate CVE-2026-3263

Immediate Actions Required

• Restrict access to the /api/Security/ endpoint to only authorized administrative users
• Implement proper role-based access control (RBAC) checks before processing Security API requests
• Review and audit all user accounts that have accessed the Security API for potential unauthorized activities
• Consider temporarily disabling the affected endpoint until a patch is available

Patch Information

The vendor was contacted regarding this vulnerability but did not respond. No official patch is currently available. Organizations using this software should implement the recommended workarounds and monitor for any vendor updates. For additional vulnerability details, see VulDB #347986.

Workarounds

• Implement network-level access controls to restrict access to the /api/Security/ endpoint to trusted IP addresses
• Add custom middleware to enforce strict authorization checks on the Security API before requests reach the endpoint
• Deploy an API gateway or reverse proxy with authorization policies to validate user privileges
• Consider replacing the vulnerable component with an alternative solution until a fix is available

# Example: Restrict access to Security API using nginx
location /api/Security/ {
    # Allow only from trusted administrative IPs
    allow 10.0.0.0/8;
    allow 192.168.1.0/24;
    deny all;
    
    # Require additional authentication header
    if ($http_x_admin_token = "") {
        return 403;
    }
    
    proxy_pass http://backend;
}