CVE-2026-3265: Free-CRM Auth Bypass Vulnerability

CVE-2026-3265 Overview

A vulnerability has been identified in go2ismail Free-CRM affecting versions up to commit b83c40a90726d5e58f0cc680ffdcaa28a03fb5d1. This security flaw affects an unknown part of the file /api/Security/ within the Security API component. The manipulation of this endpoint leads to improper authorization, allowing attackers to bypass access controls and potentially access or modify data they should not have permission to view or change.

Critical Impact

This improper authorization vulnerability in the Security API enables remote attackers to bypass authorization controls, potentially leading to unauthorized access to sensitive CRM data, customer information, and administrative functions.

Affected Products

• go2ismail Free-CRM (versions up to commit b83c40a90726d5e58f0cc680ffdcaa28a03fb5d1)
• Free-CRM Security API component (/api/Security/)
• All installations using the rolling release prior to vulnerability disclosure

Discovery Timeline

• 2026-02-26 - CVE-2026-3265 published to NVD
• 2026-02-26 - Last updated in NVD database

Technical Details for CVE-2026-3265

Vulnerability Analysis

This vulnerability is classified under CWE-266 (Incorrect Privilege Assignment), which occurs when a product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor. In the context of Free-CRM, the Security API endpoint at /api/Security/ fails to properly validate authorization for incoming requests, allowing authenticated users to access resources or perform actions beyond their intended privilege level.

The attack can be executed remotely over the network with low complexity. An attacker with low-level privileges and no user interaction required can exploit this flaw. This represents a classic Insecure Direct Object Reference (IDOR) pattern where the application does not adequately verify that the requesting user has legitimate access to the requested resource.

Root Cause

The root cause of this vulnerability lies in improper authorization checks within the Security API component. The application fails to validate whether the authenticated user has the appropriate permissions to access or modify the requested resources. This typically occurs when:

1. The application relies solely on authentication without proper authorization verification
2. Access control checks are missing or incomplete in API endpoint handlers
3. Object-level authorization is not enforced, allowing users to reference objects they should not access
4. The Security API trusts client-supplied identifiers without server-side validation

Attack Vector

The attack vector for CVE-2026-3265 is network-based, meaning attackers can exploit this vulnerability remotely. The exploitation process involves:

1. Authentication: The attacker first authenticates to the Free-CRM application with valid low-privilege credentials
2. API Discovery: The attacker identifies the vulnerable /api/Security/ endpoint
3. Parameter Manipulation: By manipulating request parameters (such as object IDs, user references, or resource identifiers), the attacker can bypass authorization controls
4. Unauthorized Access: The attacker gains access to data or functionality belonging to other users or administrative functions

Since the exploit has been publicly disclosed and is available, organizations running affected versions of Free-CRM should treat this as an active threat. Technical details are available in the GitHub IDOR Advisory.

Detection Methods for CVE-2026-3265

Indicators of Compromise

• Unusual patterns of API requests to /api/Security/ endpoints with varying object identifiers
• Access attempts to resources or data outside a user's normal scope of operations
• Sequential or enumerated object ID patterns in API request logs suggesting IDOR enumeration
• Authentication logs showing legitimate credentials accessing unauthorized resources

Detection Strategies

• Implement API request monitoring to detect unusual access patterns to the Security API endpoint
• Deploy web application firewall (WAF) rules to identify and alert on IDOR attack patterns
• Enable detailed logging for all /api/Security/ endpoint access with user context
• Correlate authentication events with authorization failures to identify potential exploitation attempts

Monitoring Recommendations

• Monitor API access logs for requests to /api/Security/ that return data inconsistent with user permissions
• Set up alerts for high-volume API requests from single users that may indicate enumeration attempts
• Review application logs for authorization bypass attempts or unexpected privilege escalation events
• Implement real-time monitoring for anomalous data access patterns in the CRM database

How to Mitigate CVE-2026-3265

Immediate Actions Required

• Restrict network access to the Free-CRM application to trusted networks only until patching is complete
• Implement additional authentication layers or access controls at the network level
• Review and audit all user accounts for unauthorized access or suspicious activity
• Consider temporarily disabling the /api/Security/ endpoint if business operations permit

Patch Information

The vendor (go2ismail) was contacted early about this disclosure but did not respond. Free-CRM adopts a rolling release strategy for continuous delivery, meaning specific version numbers for patches are not available. Organizations should monitor the official Free-CRM repository for commits that address this vulnerability post-disclosure. Additional technical information can be found at VulDB #347988.

Workarounds

• Implement a reverse proxy or API gateway with custom authorization rules to validate all requests to /api/Security/
• Add application-level access control lists (ACLs) to restrict API endpoint access to authorized users only
• Deploy network segmentation to limit exposure of the vulnerable CRM application
• Consider implementing a custom middleware or security filter that enforces proper authorization checks before requests reach the vulnerable endpoint

# Example: Nginx configuration to restrict access to vulnerable endpoint
location /api/Security/ {
    # Restrict to internal network only
    allow 10.0.0.0/8;
    allow 192.168.0.0/16;
    deny all;
    
    # Add additional authentication header requirement
    if ($http_x_internal_auth != "your-secure-token") {
        return 403;
    }
    
    proxy_pass http://freeCRM_backend;
}